1Heat oven to 350°F (325°F for dark or nonstick pan). Line 13x9-inch pan with cooking parchment paper or foil; spray paper or foil with cooking spray.
2In medium bowl, stir together all ingredients until smooth. Pour batter into pan.
3Bake 28 to 30 minutes or until toothpick inserted 2 inches from edge of pan comes out almost clean. Cool completely, about 45 minutes. Cut into 6 rows by 4 rows.