Lightly spoon flour into dry measuring cups; level with a knife. Combine flour and next 6 ingredients (flour through baking powder) in a bowl.
Combine water, oil, and eggs; add to flour mixture, stirring by hand just until moist.
Spoon the batter into a 9-inch round cake pan coated with cooking spray. Bake at 375° for 50 minutes or until a wooden pick inserted in center comes out clean. Cool rice cake for 15 minutes in pan on a wire rack, and remove from pan. Cool completely on wire rack.