Prepare cake batter and bake as directed on package for 24 cupcakes, blending 1 pkg. dry pudding mix into batter before spooning into prepared muffin cups. Cool cupcakes in pans 10 min.; remove from pans to wire racks. Cool completely.
Use small sharp knife to cut 1-1/4-inch-wide hole in top of each cupcake, being careful to not cut through to bottom of cake. Fill holes with caramel topping; cover with cupcake tops.
Melt chocolate as directed on package; cool slightly. Beat remaining pudding mix, milk and powdered sugar in large bowl with whisk 2 min.; stir in COOL WHIP. Spread frosting onto cupcakes; drizzle with chocolate. Sprinkle with salt.