Bananas Foster Sundae

Combine ice cream and chopped toffee bar in a bowl; stir well, and freeze until firm.

Meanwhile, melt butter in a medium nonstick skillet over medium heat. Stir in brown sugar and water. Cook 1 minute or until sugar dissolves and mixture begins to thicken, stirring constantly. Add banana and vanilla; cook 1 minute, stirring to coat banana. Serve banana sauce over ice cream.