HEAT oven to 350ºF.
PREPARE Dinners in large saucepan as directed on package, using the Sensible Solution directions. Stir in mozzarella and eggs.
SPOON into foil-lined 13x9-inch baking dish sprayed with cooking spray. Stand wieners, in 4 rows of 5 wieners each, in Dinner mixture for the ghouls.
BAKE 20 min.; cool 5 min. Add small dabs of mustard to wieners for the ghouls' eyes.