In a large skillet over medium heat, add the ground beef. Cook until browned, breaking it up with a spatula as it cooks, about 5-7 minutes. Drain excess fat.
To the skillet with the beef, add the chopped garlic and the white parts of the scallions. Sauté for another 2 minutes until fragrant.
Stir in the white beans, salsa, chicken broth, chili powder, cumin, and paprika. Mix well and let it simmer for about 5 minutes.
In a large baking dish, layer half of the Doritos chips on the bottom. Spoon half of the beef and bean mixture over the chips, followed by 1.5 cups of cheese. Repeat layers with remaining chips, beef mixture, and top with the rest of the cheese.
Preheat your oven to 350°F (175°C) and bake the casserole for 20-25 minutes or until the cheese is bubbly and golden.
Once out of the oven, let the casserole cool for a few minutes. Top with the green parts of the scallions, fresh tomatoes, sour cream, and lime before serving.