3/4 c. Grape-Nuts cereal, divided
2 c. chocolate low-fat ice cream, softened
1 (2.1 oz.) pkg. chocolate instant pudding mix
1/4 c. creamy peanut butter
1 c. frozen whip topping, thawed

Sprinkle 1/2 cup of cereal nuggets in bottom of 8-inch round cake pan. Combine remaining 1/4 cup cereal nuggets, ice cream, pudding mix and peanut butter in a large bowl; stir until mixture is well blended. Fold in whip topping. Spoon mixture into cake pan, spreading gently with a spatula. Cover and freeze 2 hours, until firm. Let stand at room temperature 15 minutes before serving.