2 tbsp. butter
2 c. sugar
1/2 c. vinegar
1/2 tsp. vanilla

Melt 2 tbsp. butter in heavy pan, and add 2 cups sugar and 1/2 cup vinegar. Stir until sugar is dissolved, washing down sides of pan with pastry brush dipped in cold water. Boil until mixture is brittle when dipped into cold water.

Turn into buttered flat pan and fold toward center as mixture cools around edges. Add 1/2 teaspoon vanilla.

When cool enough to handle, grease fingers with butter, grab chunks and pull and stretch until porous and light-colored. Cut in pieces with kitchen shears.