Italian Sausage and Potato Casserole

By Tyla | Last modified on Nov 24, 2025

Featured in: Dinner - Lunch

Okay, so imagine if Italian sausage, crispy roasted potatoes, sweet bell peppers, and melted mozzarella decided to have a party in a casserole dish and invited garlic, herbs, and marinara sauce to make things interesting. That’s what we’re dealing with here. Italian Sausage and Potato Casserole is basically everything you love about a good Italian meal—savory sausage with fennel and spices, golden potatoes with crispy edges, colorful peppers that get sweet and caramelized, all topped with gooey cheese and fresh herbs. It’s the kind of dish that makes your house smell like an Italian grandmother’s kitchen, even if you’re just a regular person who can barely pronounce “mozzarella.” I made this for a potluck once and someone asked if I was secretly Italian. Another person came back three times and pretended they were “just checking if anyone else wanted seconds.” This casserole inspires identity fraud and transparent selfishness.

Why You’ll Love This Recipe

One pan does everything. Minimal dishes, maximum flavor. This is lazy cooking that looks impressive.

Pure comfort food. This is what you crave when you’re cold, tired, or just need a hug in food form.

Feeds a crowd. Perfect for family dinners, potlucks, or meal prep for the week.

Budget-friendly. Sausage, potatoes, and peppers won’t break the bank. Fancy taste, not fancy price.

Customizable heat. Use sweet Italian sausage for mild, or hot sausage if you like to live dangerously.

Even better reheated. The flavors develop overnight. Next-day leftovers might be better than the original.

The Good Stuff You’ll Need

For the Casserole:

1.5 lbs Italian sausage (sweet, hot, or a mix—links or bulk)
2.5 lbs Yukon Gold or red potatoes, cut into 1-inch chunks
2 bell peppers (red, yellow, or orange work best), diced
1 large onion, diced
4 cloves garlic, minced
1 cup marinara or pasta sauce (optional but adds richness)
1.5 cups shredded mozzarella cheese
1/2 cup grated Parmesan cheese
3 tbsp olive oil
2 tsp Italian seasoning
1 tsp smoked paprika
1/2 tsp red pepper flakes (optional, for heat)
Salt and black pepper to taste
Fresh parsley for garnish

Optional Add-Ins:

Cherry tomatoes, halved
Zucchini, diced
Mushrooms, sliced
Fresh basil instead of parsley
Red onion for sweeter flavor
Kalamata olives, sliced
Sun-dried tomatoes
A splash of white wine for deglazing

Equipment:

Large oven-safe skillet or 9×13 inch casserole dish
Large mixing bowl
Sharp knife and cutting board
Wooden spoon or spatula
Aluminum foil

Let’s Do This

Step 1: Prep Your Ingredients

Preheat your oven to 400°F (200°C).

Cut potatoes into roughly 1-inch chunks. Try to keep them similar in size so they cook evenly.

Dice bell peppers and onion. Keep the pieces substantial—they’ll shrink as they cook.

Mince your garlic. Don’t use jarred garlic for this—fresh makes a huge difference.

If using sausage links, remove them from their casings. If using bulk sausage, you’re already winning.

Get all your ingredients prepped and ready. Once you start cooking, things move fast.

Step 2: Brown the Sausage

Heat 1 tablespoon of olive oil in a large oven-safe skillet over medium-high heat.

Add the Italian sausage and break it up with a wooden spoon or spatula into bite-sized pieces.

Cook for 6-8 minutes, stirring occasionally, until browned and cooked through. You want some crispy bits—those are flavor nuggets.

Don’t drain ALL the fat—leave about a tablespoon in the pan for flavor. If there’s an excessive amount (more than 2-3 tablespoons), drain some off.

Transfer the cooked sausage to a plate and set aside. Leave the flavorful bits in the pan.

Step 3: Cook the Vegetables

In the same pan with the sausage drippings, add another tablespoon of olive oil if needed.

Add the diced onions and cook for 3-4 minutes until they start to soften and become translucent.

Add the bell peppers and cook for another 3-4 minutes, stirring occasionally.

Add the minced garlic and cook for 1 minute until fragrant. Don’t let it burn or it’ll get bitter.

Season with salt, pepper, Italian seasoning, smoked paprika, and red pepper flakes if using.

If using marinara sauce, add it now and stir everything together. Let it simmer for 2-3 minutes.

Step 4: Add the Potatoes

In a large mixing bowl, toss the potato chunks with the remaining tablespoon of olive oil, salt, pepper, and a pinch more Italian seasoning.

Add the seasoned potatoes to the skillet with the vegetables. Stir everything together so the potatoes get coated with all those flavorful drippings.

Return the cooked sausage to the pan and mix everything together.

If your skillet isn’t oven-safe, transfer everything to a greased 9×13 inch casserole dish at this point.

Step 5: Bake the Casserole

Cover the skillet or casserole dish tightly with aluminum foil.

Bake covered for 35-40 minutes. The potatoes should be tender when pierced with a fork.

Check at 30 minutes—if the potatoes are tender, you’re good. If not, give them another 5-10 minutes.

The foil traps steam, which helps the potatoes cook through without drying out.

Step 6: Add the Cheese

Remove the foil and give everything a stir. Check seasoning and add more salt or pepper if needed.

Sprinkle the shredded mozzarella and grated Parmesan evenly over the top.

Return to the oven uncovered and bake for another 10-15 minutes until the cheese is melted, bubbly, and starting to get golden brown spots.

For extra golden cheese, turn on the broiler for the last 2-3 minutes. Watch it like a hawk—broilers go from perfect to burnt in seconds.

Step 7: Garnish and Serve

Remove from the oven and let it rest for 5 minutes. This helps everything set slightly and prevents burning your mouth on molten cheese.

Sprinkle generously with fresh chopped parsley. The bright green makes everything look prettier and adds freshness.

Optional: Add a little more Parmesan on top, a drizzle of olive oil, or a sprinkle of red pepper flakes.

Serve hot, directly from the skillet or casserole dish for that rustic family-style vibe.

Try not to eat half the pan standing at the stove. This is a real challenge.

Serving Suggestions

This is basically a complete meal on its own, but here are some ideas:

Serve with crusty Italian bread for soaking up all the juices
Pair with a simple green salad dressed with balsamic vinaigrette
Add a side of garlic bread or cheesy breadsticks
Serve over creamy polenta for extra comfort
Top individual servings with a fried egg for breakfast-for-dinner vibes
Pair with roasted green beans or broccoli for extra veggies
Serve with a glass of red wine (Chianti or Sangiovese work beautifully)

Switch It Up

Chicken Sausage Version: Use chicken or turkey sausage instead of pork for a lighter option.

Cheesy Overload: Add cream cheese or ricotta dollops before adding the mozzarella.

Spicy Kick: Use hot Italian sausage, add jalapeños, and use pepper jack cheese.

Creamy Style: Add 1/2 cup heavy cream or Alfredo sauce before baking for a richer dish.

Mediterranean Twist: Add artichoke hearts, Kalamata olives, and feta cheese.

Sweet Potato Swap: Use sweet potatoes instead of regular potatoes for a different flavor profile.

Keto-Friendly: Replace potatoes with cauliflower florets. Reduce cooking time by 10 minutes.

Breakfast Casserole: Add scrambled eggs before baking. Perfect for brunch.

Pizza Style: Skip the marinara, add pepperoni, and use pizza seasoning.

Storage and Make-Ahead Tips

This is a meal prep champion that reheats beautifully.

Refrigerate: Store in an airtight container for up to 4-5 days. Reheat in the oven at 350°F until warmed through, or microwave individual portions.

Freeze: Cool completely, portion into freezer-safe containers, and freeze for up to 3 months. Thaw overnight in the fridge before reheating.

Make ahead (option 1): Cook everything through step 4, don’t bake yet. Refrigerate for up to 24 hours. When ready to eat, bring to room temp for 30 minutes, then bake as directed, adding 5-10 extra minutes.

Make ahead (option 2): Fully bake the casserole, let it cool, cover tightly, and refrigerate. Reheat covered at 350°F for 25-30 minutes.

Meal prep: Portion into individual containers after baking. Perfect for grab-and-go lunches all week.

Reheat without drying out: Add a splash of chicken broth or water before reheating to keep it moist. Cover with foil while reheating.

Why This Works So Damn Well

Browning the sausage first creates a fond (those browned bits stuck to the pan) which adds massive flavor when you cook the vegetables in the same pan. Never waste that flavor base.

Using the sausage fat to cook the vegetables means you’re layering Italian sausage flavor into every component. This is flavor building 101.

Cutting potatoes uniformly ensures they all cook at the same rate. Nobody wants some potatoes raw and others mushy.

Covering during the first bake creates steam that cooks the potatoes through without drying out the sausage or vegetables. It’s like a mini oven-braising situation.

The cheese goes on last because if you add it too early, it can burn or become rubbery. Adding it at the end creates that perfect golden, bubbly cheese layer.

Yukon Gold potatoes are ideal because they’re creamy, hold their shape, and don’t fall apart during cooking. Russets work but can get mealy. Red potatoes also work great.

Bell peppers add sweetness that balances the savory, slightly spicy sausage. They also add color and vitamins, but mostly they’re just delicious.

Italian seasoning is the secret weapon. It’s a blend of oregano, basil, thyme, and sometimes rosemary. It brings authentic Italian flavor without measuring five different herbs.

When to Make This

Busy Weeknights: Prep it in the morning, bake when you get home. Dinner without stress.

Sunday Meal Prep: Make it on Sunday, eat well all week. Your future self will thank you.

Fall and Winter Comfort: When it’s cold outside and you need something warming and substantial.

Family Gatherings: This feeds a crowd and everyone loves it. Safe bet for picky eaters.

Potluck Champion: Travels well, serves in the dish it baked in, always gets compliments.

Post-Workout Fuel: Protein, carbs, and vegetables. Balanced and satisfying.

Questions People Actually Ask

Q: Can I use pre-cooked sausage? A: Yes, but you’ll miss out on the flavor from browning it yourself. If using pre-cooked, slice it and add it in step 4 with the potatoes.

Q: My potatoes aren’t cooking. What’s wrong? A: They might be cut too large, or your oven temp is off. Cut them smaller (3/4 inch chunks) or cover and cook longer. Check with a fork.

Q: Can I make this without cheese? A: Sure, but why would you want to? Just kidding—skip the cheese and add more vegetables or a drizzle of olive oil on top for richness.

Q: The bottom is burning but the top isn’t done. Help! A: Your oven might run hot, or the pan is too close to the heating element. Lower the rack position and reduce temp by 25°F.

Q: Can I add more vegetables? A: Absolutely. Zucchini, mushrooms, cherry tomatoes, and broccoli all work great. Add them when you add the bell peppers.

Q: Is this spicy? A: Only if you use hot Italian sausage or add red pepper flakes. Sweet Italian sausage makes it mild and family-friendly.

Q: Can I use frozen potatoes? A: Fresh is better, but frozen diced potatoes can work in a pinch. Skip the pre-seasoning and use them straight from frozen—they might release more water though.

Q: My casserole is dry. What happened? A: You either overbaked it or didn’t cover it during the first bake. Add some marinara sauce or chicken broth next time for moisture.

Q: Can I make this in a slow cooker? A: Yes! Brown the sausage first, then add everything to the slow cooker. Cook on LOW for 6-7 hours or HIGH for 3-4 hours. Add cheese in the last 15 minutes.