Mix unflavored gelatin and sugar in medium microwave-able bowl until well blended. Stir in soda. Let stand 3 min. or until gelatin is softened. Microwave on high 3 min. or until gelatin and sugar are dissolved, stirring after each minute. Pour into 8-inch square dish sprayed with cooking spray.
Refrigerate 25 to 30 min. or until set but not firm. Meanwhile, add boiling water to raspberry gelatin mixes in separate medium bowl; stir 2 min. until completely dissolved. Stir in cold water. Cool 15 min.
Pour raspberry gelatin gently over clear gelatin layer in dish. Refrigerate 1 hour or until firm. Cut into 36 squares; top with raspberries just before serving.
Prepare using your favorite flavor of JELL-O Gelatin.
Instead of cutting the gelatin into squares, use cookie cutters to cut it into desired shapes.
Substitute raspberry-flavored liqueur for the 1/4 cup cold water.
Save 25 calories and 7g of sugar per serving by preparing with 2 pkg. (0.3 oz. each) JELL-O Raspberry Flavor Sugar Free Gelatin.