In a large pan over medium-high heat, cook the ground beef, green pepper and onion until beef is browned and vegetables have softened (10-15 minutes).
Add the taco seasoning, garlic and salt and cook 1 minute.
Stir in the tomato sauce and salsa, and cook over medium-heat for 3-4 minutes. Set aside.
Preheat oven to 350 degrees F and lightly grease a 9x13" pan. Spread a thin layer of sauce on the bottom of the pan, then top with 3 lasagna noodles. Top with 1/4 of the remaining sauce, and 1 cup of cheese.
Repeat layers 3 more times for 4 layers total. End with remaining sauce and cheese on top.
Spray a piece of tin foil with non stick spray and place (spray side down) on the lasagna. Bake for 45 minutes.
Uncover the lasagna and bake 8-10 more minutes, until thickened and bubbly and cheese has browned slightly. Let rest for 5-10 minutes before serving.