Mix together all ingredients except arequipe or dulce de leche. Place one half of the crumb mixture into a buttered small rectangular baking pan. Press and flatten.
Spread with dulce de leche or arequipe. Top with the remaining of mixture and pat lightly.
Bake for 30-35 minutes or until light brown.
Cool slightly and cut into bars while still in the pan. Gently remove cut bars from pan.