Spicy Meatball Sub

Name: Spicy Meatball Sub
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Yield: 4
Ingredients: Ingredients; 4 large hoagie rolls or Italian sub rolls; 1 1/2 lbs ground beef (80/20 blend); 1/2 lb ground Italian sausage; 1 cup Italian breadcrumbs; 1/2 cup whole milk; 1 large egg; 1/2 cup grated Parmesan cheese; 4 cloves garlic, minced; 1/4 cup fresh parsley, chopped; 1 teaspoon red pepper flakes; 1 teaspoon salt; 1/2 teaspoon black pepper; 2 tablespoons olive oil; 8 slices provolone cheese; 1/4 cup fresh basil, chopped (for garnish); Spicy Marinara; 2 cups marinara sauce; 1 teaspoon red pepper flakes; 1/2 teaspoon cayenne pepper; 1 tablespoon brown sugar; 2 cloves garlic, minced; 1 teaspoon Italian seasoning