Weeknight Mexican Lasagna

Step 1 -Preheat the oven to 375 degrees F.

Step 2 -Coat two 9x13-inch pans with cooking spray. If you're going to freeze one casserole, be sure to use one pan that can go in the freezer.

Step 3 -In a large skillet over medium-high heat, add the beef and the onion and cook, while crumbling the beef, until the meat is no longer pink, about 5-7 minutes.

Step 4 -Drain the grease from the skillet.

Step 5 -In a large bowl, add the beef mixture, the refried beans, and the taco seasoning and stir to combine.

Step 6 -In each of the prepared pans, layer about 1/4 of the beef mixture, 1 cup of the cheese, 1/4 of the green peppers, and 3 of the tortillas.

Step 7 -Evenly divide the remaining beef mixture between the two pans and top both with 1 cup of the cheese; then evenly divide the remaining green peppers between the two pans and top each of them with 3 of the tortillas.

Step 8 -Top each of the casseroles evenly with the remaining cheese, the green onions, and the diced tomatoes.

Step 9 -If you're freezing one casserole, cover it with plastic wrap and then aluminum foil and place in the freezer. With the casserole you're serving immediately, cover it with aluminum foil.

Step 10 -Bake, covered, until the cheese is melted and the casserole is heated through, about 45 minutes.

Step 11 -Serve with the sour cream.