Separate ground beef into 8 equal-sized patties and season with freshly ground black pepper and kosher salt.
Slice bell peppers into 1/2” wide strips.
Set the grill — as well as your side burner — to medium heat.
Place a pan on your side burner, add 2 tablespoons of olive oil to it and add the peppers. Grill for 15 minutes, stirring them every few minutes. If you don’t have a side burner you can grill them in a grill pan or even on aluminum foil right on your grill along with the burgers.
Grill burgers for 5 minutes per side or until they reach your desired level of doneness. Add cheese for the last minute on the grill. If you want to toast your buns place those on the grill for the final minute as well.
To make the guacamole slice the avocados in half, remove the pits and skin and mash the avocado in a mixing bowl until it reaches your desired consistency. Add mayonnaise, garlic powder, onion powder and stir to combine.
Assemble your burgers by spreading guacamole on the bottom bun, topping with a burger, bell peppers, your choice of condiments (I went with sour cream and nacho cheese) and finally the top bun.