Preheat oven 375 degree. Grease an 8-inch baking pan.
Put all ingredients in a mixing bowl. Using a wooden spoon, stir until well combined. Spread the mixture evenly in the prepared pan.
Bake for 14 to 16 minutes, until the edges are brown and the center is set. Watch closely and be careful not to overbake; checking at the 14 minutes because the cookie can burn easily.
Allow to cool completely in the pan before cutting into 12 bars. (they will firm up as they cool.) Leftovers can be stored in an airtight container for up to a week.