PREHEAT oven to 375°F. Stir together 1 cup flour, granulated sugar, baking powder and salt. Cut in 3 Tbsp. butter to form crumbly mixture.
COMBINE egg and coffee; add to flour mixture, mixing just until blended. Pour into greased 8-inch square baking pan.
MIX brown sugar and 3 Tbsp. flour. Cut in 3 Tbsp. butter until mixture is crumbly. Stir in cereal. Sprinkle topping over cake batter. Bake 30 to 35 min. or until toothpick inserted in centre comes out clean. Serve warm.