English Toffee Bars
2 sticks butter, softened
1 cup packed dark brown sugar
1 large egg, separated
2 cups all-purpose flour
1 cup slivered or sliced almonds
Preheat the oven to 275 degrees. Coat a 15x10-inch rimmed baking sheet with cooking spray. In the large bowl of an electric mixer, beat the butter and sugar until creamy. Add the egg yolk (reserve the white) and mix. Blend the flour into the creamed mixture to make a stiff cookie dough. Press the dough evenly over the bottom of the baking pan. Beat the egg white lightly and then brush it over the dough to cover evenly. Sprinkle the almonds over the top and press in lightly.
Bake for one hour or until firm when lightly touched. While still hot, cut into 1.5 inch squares. Let cool in the pan on a rack.