In a large mixing bowl, thoroughly combine all the meats, Italian Seasoning, garlic and onion powder.
Shape meat mixture into six individual burgers.
Place burgers in the refrigerator for about 15 minutes before you grill them.
Meanwhile, in a small saucepan, heat the marinara sauce to a slow simmer, stirring occasionally.
On a flat grill pan or large skillet, fry the slices of pepperoni. They will cook very quickly and give off a lot of grease. Turn each slice carefully after 30-45 seconds on each side and then move to a paper towel lined plate to drain. Drain off all the pepperoni grease except for two tablespoons.
When you're ready to cook the burgers, use the same flat pan on medium high and cook the burgers in the leftover pepperoni fat.
Grill the burgers for approx 3 - 5 minutes per side depending on how thick your burgers are and how you like them cooked. I did ours for about 4 minutes per side and they were perfect!
While the burgers are cooking, in a small microwave bowl, melt the butter with the minced garlic. Brush the melted butter over the tops of the Telera Rolls and sprinkle each roll with 1 Tablespoon grated parmesan. Separate the top and bottom buns and place them under the broiler on low, until the tops are golden brown and the bottoms are crisp and toasty.
Flip the burgers one more time and top each burger with two slices of Mozzarella cheese. Allow the cheese to melt, then remove from heat.
Assemble the burger by spreading marinara sauce on the bottom bun, place the burger on the bottom bun then top with two slices fried pepperoni, slices of red onion, a few fresh basil leaves and more marinara if desired. Add garlic butter parmesan top and enjoy!