Preheat oven at 400 degrees Fahrenheit.
Start by prepping all veggies: Julienne bell peppers, thinly slice mushrooms and measure out 1 cup, half cherry tomatoes, thinly dice yellow onion, mince garlic, and thinly slice baby spinach.
Place cast iron pan on stove-top and drizzle olive oil over it. Turn stove on medium-high heat and bring oil to a heat. Add diced onion and minced garlic. Sauté for 1-2 minutes until onion begins to translucent. Toss in mushrooms and bell peppers and sauté for about 2-3 minutes until bell peppers start to slightly soften and mushrooms start to slightly brown. Stir in halved tomatoes and continue to saute for 1-2 minutes until tomatoes start to soften a bit. You want veggies to cook a bit to get juices flowing and flavors running. You don't want to overcook them since they will be baked within the omelette muffins. Sprinkle veggies with salt and pepper to taste if desired. Remove veggies from heat and set aside.
In a large mixing bowl, combine chickpea flour, nutritional yeast, turmeric, curry powder, cumin, paprika, baking powder and pink sea salt. Whisk dry ingredients together. Once all dry ingredients are well combined, pour in water and continue to whisk until batter is formed and there are no traces of flour. Fold in cooked veggies and baby spinach and continue to whisk until these are well combined.
Generously grease a 6 tin muffin pan. Pour batter into muffin pan filling to the top of each mold. Careful to not over fill so that batter doesn't overflow as you transport pan into oven. Bake omelette muffins for 25 minutes.
Turn oven off but do not open oven door. Allow muffins to remain in closed oven for another 10 minutes.
Remove muffins from oven and let them cool-down for another 10 minutes.
Remove muffins from pan. Use a table knife if needed to help pop them out. Place on cooling rack and allow muffins to continue to cool-down for another few minutes.
Serve and enjoy! Store any leftover Chickpea Omelette Muffins in the fridge for 3-5 days.