Spinach Bacon Quiche

I got this recipe here

I just use a pre-made refrigerated pie crust

Or I can make this crust
Ingredients
1 cup + 2 TBS flour
1/2 tsp salt
1/3 cup butter (super soft, even a little melted)
3 TBS milk

Mix all together with a fork.

Ingredients for filling
(I use a bottle of bacon bits) 4 strips bacon (optional)
1 large onion, chopped
1 clove garlic, minced
(I use half a bag of frozen spinach) 6 to 8 ounces spinach leaves, stemmed and coarsely chopped
3 large eggs
1 1/3 cups half-and-half or whole milk
1 teaspoon Dijon mustard
1/2 teaspoon salt
1/4 teaspoon black pepper

Instructions
Cook the bacon in a large skillet until crispy and then transfer it to a plate. Drain all but about 2 tablespoons of the fat from the pan. If you're not using bacon, simply heat 2 tablespoons of vegetable oil in a large skillet and proceed. Add the onion and sauté it over medium heat for about 8 minutes, until clear. Stir in the garlic and spinach. Cover and steam the vegetables for about 3 to 5 minutes, stirring once or twice, until tender. Remove the pan from the heat.
Whisk the eggs in a large bowl, and then blend in the half-and-half, mustard, salt, and pepper. Spread the cooked vegetables evenly in the pie shell and sprinkle on about half of the cheese. Crumble the bacon and add it. Now slowly ladle the egg mixture over the filling and sprinkle on the remaining cheese.
Bake the quiche at 375º F on the center oven rack for about 40 to 45 minutes, until slightly puffy and golden brown. Transfer the pan to a wire rack and cool for at least 30 minutes. Serve warm, at room temperature, or cold. Be sure to refrigerate any leftovers. Makes 8 servings.