In a microwave or in a large saucepan over low heat, melt marshmallows, oil and flavoring; stir until smooth. Remove from heat; stir in cereal and half bacon. Press mixture into a lightly-greased 13x9-in. baking pan using wax paper or a lightly-greased spatula. Sprinkle with remaining bacon; press lightly into treats. Cool to room temperature. Cut into bars.