Preheat broiler. Bring 2 quarts water to a boil in 3-quart saucepan. Meanwhile, cook ground beef in large nonstick skillet over medium-high heat 5 to 6 minutes or until no longer pink.
Meanwhile, cut peppers in half lengthwise; remove stems and seeds. Add 4 pepper halves to boiling water; cook 3 minutes or until bright green and slightly softened. Remove and drain upside down on plate. Repeat with remaining 4 halves. Set aside.
Add beans, tomatoes and Mexican seasoning to ground beef. Cook and stir over medium heat 5 minutes or until mixture thickens slightly.
Arrange peppers, cut side up, in 13X9-inch baking dish. Divide chili mixture evenly among peppers; top with cheese. Broil 6 inches from heat 1 minute or until cheese is melted. Serve immediately.