Ground beef can contain up to 30 percent fat, so be sure to read the labels before purchasing. Ground round, which is between 11 percent and 15 percent fat, has just enough fat to make a tender burger.
Combine first 5 ingredients in a medium bowl; stir in 1/4 teaspoon salt. Set aside until ready to serve.
Combine beef, green chiles, taco seasoning, and remaining 1/4 teaspoon salt in a large bowl; stir well. Divide mixture into 8 equal portions, shaping each into a 1/2-inch-thick patty.
Heat a large nonstick skillet over medium heat; coat pan with cooking spray. Add 4 patties, and cook 6 minutes on each side. Top each patty with 1 tablespoon cheese, and cook 2 minutes or until burgers are done and cheese melts. Remove from pan; keep warm. Repeat procedure with remaining patties and cheese. Serve with salsa.