Preheat oven to 350°.
To prepare cake, lightly spoon flour into dry measuring cups, and level with a knife. Combine flour, baking powder, baking soda, and salt in a small bowl, stirring with a whisk.
Place 1/2 cup sugar, almond paste, and 2 tablespoons butter in a large bowl; beat with a mixer at medium speed until well blended. Add egg and lemon juice, beating well. Add flour mixture and fat-free milk alternately to sugar mixture, beginning and ending with flour mixture. Fold in blueberries and rind. Spoon batter into a 9-inch square baking pan coated with cooking spray.
To prepare topping, combine 1/4 cup sugar and remaining ingredients in a small bowl, tossing with a fork until moist. Sprinkle topping evenly over batter. Bake at 350° for 35 minutes or until a wooden pick inserted in center comes out clean. Cool in pan on a wire rack.
Almond paste is found in the baking section of the grocery store. (Don't substitute marzipan, which is sweeter and has a smoother texture.) If it is hard, soften it by microwaving at HIGH 10 to 15 seconds.