Preheat the Oven:
Preheat your oven to 375°F (190°C). Grease a 9-inch pie dish or baking dish with butter or nonstick spray.
Prepare the Egg Mixture:
In a large mixing bowl, whisk together the eggs, milk, and cream until well combined. Season with salt, pepper, and any optional seasonings.
Layer the Ingredients:
Spread the cooked vegetables and protein evenly across the bottom of the prepared dish. Sprinkle shredded cheese on top.
Add the Egg Mixture:
Pour the egg mixture over the layered ingredients, ensuring everything is evenly coated.
Bake the Quiche:
Place the dish in the preheated oven and bake for 30–35 minutes, or until the quiche is set in the center and lightly golden on top. A knife inserted into the center should come out clean.
Cool and Serve:
Allow the quiche to cool for 5–10 minutes before slicing. Garnish with fresh herbs if desired, and serve warm or at room temperature.