Melt butter in large skillet over medium-high heat. Add onion and mushrooms; cook and stir 3 minutes. Add rice, garlic powder and pepper; cook 2 minutes.
Stir in 1 can of the broth; cook 4 minutes, stirring constantly. Gradually stir in remaining can of broth; cook 7 minutes or until liquid is almost absorbed, stirring frequently.
Stir in whipping cream. Remove from heat. Stir in 1/3 cup cheese. Spoon into serving dish; sprinkle with 1 tablespoon cheese.