Heat oven to 375°F. In large nonstick skillet, cook ground beef, onions and garlic until beef is thoroughly cooked, stirring frequently. Drain. Add green chiles, salt and pepper; mix well. Remove from heat.
Pour 1 can of the enchilada sauce in bottom of ungreased 13×9-inch (3-quart) glass baking dish. Arrange 4 tortillas in dish, overlapping slightly. Spoon beef mixture evenly over tortillas; top with remaining 4 tortillas. Pour remaining can of enchilada sauce over top. Sprinkle with cheese.
Bake at 375°F. for 20 to 25 minutes or until thoroughly heated. Serve with sour cream.