Prepare a grill fire to 350° using hickory or pecan for smoke flavor.

Divide ground beef into 12 patties and season with 2 teaspoons salt and 2 teaspoons pepper. 

Grill burgers over indirect fire for about 5 minutes with the grill closed. 

Flip the burgers and continue to cook another 5- 8 minutes until internal temperature reaches 165° using a digital meat thermometer. 

Remove burgers to a sheet pan. 

For pizza sauce, add tomato sauce to a small bowl with brown sugar, 1 teaspoon marjoram, 1/2 teaspoon each of thyme, oregano, basil, rosemary, garlic, salt and pepper. Mix well.

Make the butter sauce in a small skillet. Add butter, Worcestershire sauce, dijon mustard, onion flakes, granulated garlic and pepper. Cook over low heat until butter is melted, whisk mixture together and remove from heat.

Slice rolls in half and place on a foil line grill pan.

Brush the bottom of the rolls with butter mixture.

Top with burger patties.

Spoon pizza sauce over burgers and top with shredded mozzarella.

Add top buns.

Brush or spoon remaining butter mixture over the tops of the sliders.

Return to the grill for about 10 minutes with the grill lid closed or until buns are toasted and cheese is melted. 

This step can also be done in a 375° oven for about 10 minutes.

Serve immediately.