Lay out the wonton skins one at a time. Place one piece of string cheese in the centre near the edge then arrange some pepperoni, sliced mushrooms and garlic around the cheese. Roll up the wonton skin a little, fold in the sides then continue to roll up and seal the edge by moistening with water. Repeat with remaining skins, cheese and fillings.
Heat oil in a large heavy frypan. Fry in batches, turning once after about 5 minutes. Continue to fry for 3 to 5 more minutes or until golden brown. Drain on paper towels.
Warm the pasta sauce in a serving bowl in the microwave. Serve on a platter with the bowl of sauce for dipping.