Stir boiling water into the flavored Jell-O gelatin, stir until dissolved. Cool to room temperature, about 35 minutes. Pour the milk into another bowl; add Instant pudding mix. Beat with a wire whisk until well blended about 2 minutes. Quickly pour into the gelatin mixture; stir with whisk until well blended. Pour into a 9x13-inch pan lined with foil-over hanging on ends and sprayed. Chill until firm 3 hours or more( I do overnight). Lift foil gently out from pan. Fold down edges. Cut into shapes with cookie cutters or cut into squares. Use flat spatula to remover pieces to serving plate. Keep chilled any leftovers.
Flavor of Jell-o and pudding can be changed to suit your taste buds.