Saute broccoli, bell peppers and onion in a cast iron skillet or frying pan in about a teaspoon of oil. (I saute each veggie separately as I like them cooked to different degrees. I cook my broccoli until the edges are just browned, pepper just slightly, so they still have some bite, about 1 -2 minutes, and onion until slightly browned.)
Place vegetables into the crust.
Beat together the eggs, milk, and salt in a bowl.
Pour egg mixture over veggies.
Bake 25-30 minutes, until an inserted knife comes out clean.
Notes
Milk: Use any dairy-free milk you like for this recipe. Regular milk can be used if you don't need to be dairy-free.
Sun-Dried Tomatoes: For sun-dried tomatoes, look for a brand with no added ingredients or make your own.
Mini Quiche Option: Make this quiche in a mini muffin tin or cut into squares after baking it in a baking pan.
Cauliflower Crust Option: You can substitute cauliflower rice for the quinoa and flour in the crust. Simply cook the cauliflower rice, squeeze out as much of the water as possible, add in the remaining crust ingredients and proceed.