Melt butter and chocolate in a medium saucepan over low heat. Once melted, remove from heat.

Stir in brown sugar until well-dissolved, and cool to lukewarm.

Add egg and vanilla, and mix well.

Combine flour, baking powder and salt. Then, stir into chocolate mixture until blended. Stir in chips.

Spread into a greased 9-inch square baking pan. Bake at 350 degrees F for 22-27 minutes, or until a toothpick comes out clean.

Cool in pan on wire rack. Cut into squares, and serve after dinner or arguments.