Preheat oven to 350°F (175°C). Grease an 11×7-inch baking dish.
In a large skillet over medium-high heat, brown 1 1/2 pounds organic ground beef until no pink remains. Drain excess fat.
Return the beef to the skillet. Add 1 teaspoon seasoned salt, 1 package taco seasoning, 1 can (14.5 oz) petite diced tomatoes (undrained), 1 can (15 oz) tomato sauce, and 1 can (4 oz) chopped green chilies. Reduce heat to medium-low and simmer uncovered, stirring occasionally, for 15–20 minutes.
While the meat simmers, lightly beat 2 eggs in a small bowl, then stir in 2 cups (16 oz) 4% cottage cheese until combined.
Tear the 12 small corn tortillas into pieces (they should be in torn pieces as listed).
Divide the meat sauce, torn tortillas, cottage cheese mixture, and shredded cheese into two equal portions. (The shredded Cheddar & Monterey Jack cheese total is 3½–4 cups; divide evenly between the two layers.)
Assemble in the greased 11×7 dish: spread half of the meat sauce in the bottom, scatter half of the torn tortillas over the sauce, spread half of the cottage cheese and egg mixture evenly, and top with half of the shredded cheese.
Repeat the layers: remaining meat sauce, remaining torn tortillas, remaining cottage cheese and egg mixture, and remaining shredded cheese.
Bake uncovered at 350°F for 30 minutes, or until the casserole is hot and bubbly and the cheese is melted.
Remove from the oven and let stand for 5 minutes.
Top with 2–3 cups tortilla chips (broken into medium/large pieces), 3 avocados cut into chunks, 3 tomatoes diced, and salsa of your choice.
Serve immediately.