In a bowl with an electric mixer cream the butter with the sugar and beat the mixture until it is light and fluffy. Add the peanut butter, beat the mixture until it is combined well, and beat in the egg, the vanilla, and the salt. Add the flour, beat the mixture until it is just combined, and stir in the coconut. Spread the mixture evenly in a buttered jelly-roll pan, 15 1/2 by 10 1/2 by 1 inches, sprinkle the peanuts over it, pressing them into the mixture lightly, and bake the mixture in the middle of a preheated 350F. oven for 20 to 25 minutes, or until a tester comes out clean. Let the mixture cool completely in the pan on a rack, cut it into 24 bars, and cut each bar in half diagonally to form 2 triangles.

Makes 48 cookies.