• 1/2 cup about 112 grams butter
• 1 cup brown sugar firmly packed
• 1 egg
• 1/2 tsp. vanilla extract
• 2 cups sifted all-purpose flour
• 3/4 tsp. baking powder
• 3/4 tsp. baking soda
• 1/4 tsp. salt
• 1/3 cup sour cream
• 1 3/4 cups coarsely chopped cashew nuts

Ingredients for frosting:

• 1/2 cup butter
• 1 Tbsp. instant coffee powder
• 1/4 tsp. vanilla extract
• 2 cups confectioner's sugar