01 -
Preheat oven to 175°C. Lightly coat a 23 x 33 cm baking dish with nonstick spray.
02 -
Place Doritos in a large resealable bag. Gently crush to obtain 140 g of fine crumbs (about 2 cups) and 35 g of coarser pieces (about 1 cup); set both aside separately.
03 -
In a large skillet over medium heat, cook the ground beef and diced yellow onion until meat is browned and onions are soft. Drain excess fat.
04 -
Add minced garlic to the skillet and sauté for 1 minute. Stir in taco seasoning, frozen corn, diced tomatoes with green chilies, and finely crushed Doritos. If using, fold in black beans. Mix until well combined.
05 -
Remove skillet from heat. Stir in sour cream and 230 g of shredded cheese until evenly distributed.
06 -
Transfer mixture to the prepared baking dish. Bake on the center rack for 5 minutes until heated through.
07 -
Sprinkle remaining 110 g cheese over casserole, then top with coarser crushed Doritos. Return to oven and bake for an additional 5 minutes, or until cheese is melted and topping is golden.
08 -
Remove from oven and allow to rest briefly. Top with green onions, diced tomatoes, shredded lettuce, avocado, and a dollop of sour cream, if desired. Serve warm.