3 tablespoons nonfat evaporated milk
1 cup sweetened coconut flakes
1/3 cup butter
1/3 cup packed light brown sugar
3 tablespoons distilled white vinegar
1/3 cup margarine
1 cup butter, melted
1 cup milk
1/4 teaspoon vanilla extract
Line a 12 x 9 inch dish with foil. Place nonfat evaporated milk, coconut flakes and butter in foil and refrigerate overnight.
In a large bowl, beat together brown sugar, coconut vinegar and margarine. Gradually beat in milk, stirring constantly with small spoon. Beat in butter and milk.
Spread evenly into prepared serving dish. Cut the remaining 1/3 cup butter into one-quarter inch chunks and crack the remaining coconut over top. Sprinkle evenly over coconut. Spread remaining coconut over coconut and serve with remaining coconut.