1 c. brown sugar, firmly packed
1 c. granulated sugar
1/2 c. water
1/2 c. dark corn syrup
1/4 c. (1/2 stick) butter
1/2 tsp. maple flavoring
1 1/2 c. walnut pieces

Combine brown sugar, granulated sugar, water and syrup in large heavy saucepan over medium heat. Stir to dissolve sugar. Bring to boiling, stirring constantly. Continue cooking, without stirring until candy thermometer registers 300 degrees (a teaspoon of syrup will separate into hard brittle threads when dropped into cold water.) Meanwhile, butter or coat large cookie sheet with nonstick cooking spray. Remove syrup from heat. Stir in butter and maple flavoring; stir in walnuts. Quickly pour on prepared sheet. Spread thin with buttered metal spatula. Cool. Break into pieces. Store at cool room temperature in airtight container with waxed paper between layers.