Set oven control to broil. Place bread slices on ungreased cookie sheet.
Spray bread with cooking spray; sprinkle with cheese. Broil with tops 4 to
6 inches from heat 1 to 2 minutes or until light brown; set aside.

Cut beef into thin strips (beef is easier to cut if partially frozen,
about 1 1/2 hours). Heat oil in 10-inch nonstick skillet over medium-high
heat. Cook beef, bell pepper and garlic in oil, stirring occasionally,
until beef is brown. Stir in tomatoes, pizza sauce and mushrooms. Cook 2
to 4 minutes or until hot.

Place 2 toasted bread slices on each of 4 serving plates; top with beef
mixture.