Preheat your oven to 350°F (175°C).

Roll out your pie crust and gently place it into a deep-dish pie plate. Par-bake the crust for 7 minutes, then take it out and lightly press the sides with a fork to help it stay in place.

Sauté the vegetables and protein.

In a skillet over medium heat, melt the butter. Add the chopped onion and cook for about a minute. Toss in the bell peppers and green onions, sautéing for around 5 minutes. Season with salt and pepper, then stir in the chopped Canadian bacon, tomatoes, and spinach. Cook for a few more minutes until the spinach wilts. Remove from heat and let it cool slightly.

Mix the egg filling.

In a separate bowl, whisk together the eggs, flour, and heavy cream (don’t worry if it’s not perfectly smooth). Fold in the shredded cheddar cheese.

Combine and assemble.

Add the sautéed veggie mixture into the egg and cheese mixture, stirring gently until everything is evenly combined.

Bake the quiche.

Pour the filling into the pre-baked crust. Place the pie dish on a baking sheet to catch any spills. Bake for 40 to 50 minutes, or until the center is set and the top is lightly golden.

Let it cool.

Allow the quiche to rest for 10 to 15 minutes before slicing and serving.