Preheat oven to 400°F (200°C).
Toss diced sweet potatoes with 1 tablespoon olive oil, salt, and black pepper. Spread on a baking sheet and roast for 20-25 minutes, stirring halfway, until tender and golden.
In a saucepan, combine rinsed quinoa and water. Bring to a boil, then reduce to a simmer, cover, and cook 15 minutes until water is absorbed. Remove from heat and let stand covered for 5 minutes, then fluff with a fork.
Heat remaining 1 tablespoon olive oil in a large skillet over medium heat. Add chopped onion and garlic and sauté for 2-3 minutes until translucent.
Add crumbled tofu, turmeric, smoked paprika, cumin, black pepper, and salt to the skillet. Cook while stirring for 5-7 minutes until heated through and lightly golden.
Sprinkle optional black salt over tofu scramble for eggy flavor if desired.
Add spinach to the skillet and sauté for 1-2 minutes until just wilted. Adjust seasoning to taste.
Divide quinoa among four bowls. Top with tofu scramble, roasted sweet potatoes, and avocado slices. Garnish with green onions and fresh herbs.
Serve immediately while warm.