Preheat oven to 350°. Line 13 x 9-inch baking pan with aluminum foil, then grease and flour foil; set aside.
Melt Country Crock® Spread and chocolate squares in 3-quart saucepan over low heat, stirring occasionally. Remove from heat. Stir in sugar, then eggs, one at a time, and vanilla. Stir in flour and baking powder just until blended. Spread batter into prepared pan, then sprinkle with chocolate chips.
Bake 30 minutes or until toothpick inserted in center comes out clean. Cool completely on wire rack. Lift cake by foil ends onto cutting board and cut into 12 squares.