Preheat your oven to 375°F (190°C). Grease a 12-cup muffin tin with olive oil or cooking spray.
In a medium bowl, whisk together chickpea flour and water until smooth.
Add nutritional yeast, garlic powder, turmeric, and black salt. Mix well and set aside.
Heat olive oil in a frying pan over medium heat. Add the chopped bell peppers, spinach, onions, and mushrooms. Sauté the veggies for 5-7 minutes until soft and fragrant. Season with salt and pepper.
Spoon the sautéed veggies into each muffin cup, filling them about halfway.
Pour the chickpea flour mixture over the vegetables in each muffin cup, filling them nearly to the top.
Bake in the preheated oven for 25-30 minutes, or until the tops are firm and golden brown.
To check, gently press the center of one of the omelets; it should feel firm and spring back.
Allow the omelets to cool for a few minutes before removing them from the muffin tin.
Serve warm with fresh herbs, avocado, or your preferred topping.