Mushroom and Provolone Patty Melts

Ingredients     1 pound ground sirloin     Cooking spray     1 tablespoon olive oil     1/4 cup thinly sliced yellow onion     1/8 teaspoon salt     1/8 teaspoon black pepper     1 (8-ounce) package sliced cremini mushrooms     1 1/2 teaspoons all-purpose flour     1/4 cup dark beer (such as porter)     8 (1.1-ounce) slices rye bread     4 (3/4-ounce) slices reduced-fat provolone cheese Preparation     1. Heat a large nonstick skillet over medium-high heat. Shape beef into 4 (4-inch) patties. Coat pan with cooking spray. Add patties; cook 4 minutes on each side or until done.     2. Heat oil in a medium skillet over medium-high heat. Add onion, salt, pepper, and mushrooms; sauté 3 minutes. Sprinkle flour over mushroom mixture; cook 1 minute, stirring constantly. Stir in beer; cook 30 seconds or until thick. Remove from heat; keep warm.     3. When patties are done, remove from large skillet. Wipe pan clean; heat over medium-high heat. Coat 1 side of each bread slice with cooking spray. Place 4 bread slices, coated sides down, in pan. Top each with 1 patty, 1 cheese slice, and one-fourth of mushroom mixture. Top with remaining bread slices; coat with cooking spray. Cook 2 minutes on each side or until browned.