Easy Enchilada Casserole

Preheat your oven to 375 degrees F and grease a 9x13 inch baking dish with cooking spray or butter. In a large skillet over medium-high heat, cook the ground beef and diced onion together, breaking up the meat with a wooden spoon, for about 8-10 minutes until the beef is browned and no pink remains. The onions should be soft and translucent. Drain any excess fat from the pan. Add the minced garlic and cook for another minute until fragrant. Stir in the taco seasoning according to package directions, usually with a bit of water. Add the drained black beans and corn, stirring to combine. Let the mixture simmer for 2-3 minutes to allow the flavors to meld. Remove from heat and set aside.

In a medium bowl, mix together the enchilada sauce and sour cream until smooth and well combined. This creamy enchilada sauce is what makes the casserole rich and delicious, coating every layer. The sour cream mellows the spice of the enchilada sauce while adding richness. If you prefer a spicier casserole, you can skip mixing in the sour cream and layer it separately, or use a spicier enchilada sauce. Stir in the diced green chiles for extra flavor and a mild kick. Set this sauce mixture aside for layering.

Now you are ready to assemble the casserole. Start by spreading about 1/2 cup of the enchilada sauce mixture on the bottom of your prepared baking dish - this prevents the tortillas from sticking and adds moisture. Arrange 4 corn tortillas over the sauce, overlapping them slightly to cover the bottom of the dish. You may need to tear some tortillas to fill gaps. Spread half of the meat mixture evenly over the tortillas. Drizzle about 1/3 of the remaining sauce over the meat, then sprinkle with 1 cup of the shredded cheese. The cheese creates delicious melted layers throughout the casserole.

Repeat the layering process: add another layer of 4 tortillas, the remaining meat mixture, another third of the sauce, and another cup of cheese. This creates substantial layers that hold together when you slice and serve the casserole. The multiple layers ensure every bite has tortillas, meat, sauce, and cheese in perfect proportion. For the final layer, arrange the last 4 tortillas on top, spread with the remaining sauce, and finish with the remaining cup of cheese. The top layer of cheese will melt and brown beautifully in the oven, creating an irresistible golden crust.

Cover the baking dish tightly with aluminum foil. Place in the preheated oven and bake for 25 minutes. The foil keeps moisture in and helps the tortillas soften as they absorb the sauce. After 25 minutes, remove the foil and continue baking uncovered for an additional 10-15 minutes until the cheese on top is melted, bubbly, and lightly golden brown around the edges. The casserole should be heated through completely - you can insert a knife in the center and it should come out hot. Let the casserole rest for 5-10 minutes after removing from the oven. This resting time allows the layers to set slightly, making it much easier to cut clean squares.

Cut the enchilada casserole into squares and serve hot. Top each portion with your favorite garnishes - fresh chopped cilantro, sliced jalapeños, diced tomatoes, extra sour cream, sliced avocado, or a squeeze of lime juice. The garnishes add freshness and brightness that complement the rich, cheesy casserole. Serve with Mexican rice, refried beans, or a simple green salad on the side. This casserole is perfect for feeding a crowd and tastes even better the next day as the flavors continue to meld. Leftovers can be stored covered in the refrigerator for up to 4 days and reheated in the microwave or oven. You can also assemble the casserole a day ahead, cover tightly, and refrigerate until ready to bake - just add 5-10 minutes to the covered baking time if starting from cold.