Add chicken breast to a crockpot.
Season with salt, pepper, onion powder, Italian seasoning, and red pepper flakes.
Add minced garlic and 1 jar of your favorite marinara/pasta sauce.
Cook on low for 4-6 hours.
Shred chicken and add 1/4 cup shredded Parmesan cheese.
Spread butter on sub rolls and lightly season with salt and some garlic powder.
Bake at 400 degrees until the bread is toasted.
Scoop marinara chicken onto sub rolls and top with provolone cheese.
Put the sandwiches back in the oven under broil just until the cheese melts. Keep an eye on it so it doesn’t burn!
Enjoy!