1/4teaspooncayenne pepper, 1/2 teaspoon if you want more heat
Place a cast iron flattop griddle on the grill. Heat the grill to 350-450 degrees.
Meanwhile, place the pork rinds into a food processor and puree until a bread crumb consistency is developed.
Combine the beef, salt, garlic powder, Worcestershire, mayonnaise, pork rind crumbs and egg into a large bowl. With your hands combine the meat mixture.
Form into 2 1/2 inch round balls and place on a parchment lined rimmed baking sheet.
Place 2 tablespoons butter on the griddle. Once the butter is melted, create a small pile of onions for each burger you plan to cook.
Then add the meat balls on top of the onions. With a spatula (or a hamburger press) smash the patty. Cook for 1 minute and flip. Place the cheese on top of the patty and cook the remaining side for an additional minute.
Remove the patties from the grill and continue this process until all meat balls have been cooked.
Add the bun halves to the griddle, and cook interior side facing down.
Once the buns are golden, add a hearty smear of mustard to the buns and add one to two patties to each bun. Serve warm.
For the spicy yellow mustard
Place all ingredients into a small bowl. Stir to combine.
When working with ground raw meat, I prefer to wear rubber gloves. It helps with cleanup. Thin buns work best with these burgers. If the buns are too thick, cut a sliver of the center out.