Begin heating a sandwich press (a skillet will work just fine as well).
Drain tuna and add to a large bowl. Mix in yogurt, mayo, chopped pickles, parsley, chopped onion, and pepper. Mix well.
Slice tomatoes. Fill 2 tortillas with an even amount of tuna mixture, 3 slices of provolone, and a few slices of tomato; top with second tortilla. Place each tortilla into heated sandwich press and cook for 2-3 minutes or until cheese melts.
Remove and cut into quarters. Serve every two slices with an apple.