Generously butter the insides of the hamburger buns with softened butter. Set aside.
Place the ground beef in a medium bowl. Add the garlic powder, onion powder, paprika, salt, and pepper. Stir until combined.
Divide the seasoned beef into 4 portions and form patties that are about ½-inch thick.
Preheat the grill to medium heat. Place the beef patties directly on the hot grill. Cook for 3 to 5 minutes and flip with a spatula. Cook for 3 to 5 more minutes, applying the cheese slices the last 1 to 2 minutes so it can melt. The internal temperature of beef should be 160˚F.
Place the buns, buttered side down, on the grill and grill until toasted, about 1 minute. Remove from the grill.
To assemble the burgers, top the bottom of the buns with lettuce. Add the burger patties, tomato slices, guacamole, and bacon. Add the bun tops. Serve immediately.