Set your oven to 375°F (190°C). Place the pie crust in a 9-inch pie dish, pressing gently along the sides. Prick the bottom with a fork to prevent puffing, and set aside.

Heat olive oil in a skillet over medium heat. Add chopped onions and bell peppers. Cook until softened and fragrant, about 3–4 minutes.

Add the ground sausage to the skillet. Cook until browned, breaking it into small crumbles. Drain off excess fat if needed.

In a separate bowl, whisk together the eggs, milk, salt, and pepper until smooth.

Spread the cooked sausage and vegetable mixture evenly over the pie crust. Top with shredded Monterey Jack cheese, then pour the egg mixture over everything.

Bake for 30–35 minutes, or until the filling is set and the top is golden brown. The pie should feel firm in the center when gently shaken.

Allow to rest for 10 minutes before slicing.