In a small bowl, mix the house sauce with Worcestershire sauce, fish sauce, smoked paprika, salt, and pepper. In a large bowl, combine ground beef with this mixture and form into 4 evenly sized balls. Chill for 20 minutes.

Heat a skillet over medium-high heat. Melt butter and toast buns until golden. Remove and set aside.

Place beef balls on the hot skillet. Using a spatula or burger press, smash each ball into a thin patty. Season with salt and pepper. Cook for 2-3 minutes per side until crispy.

During the last minute of cooking, top each patty with a slice of cheese and allow to melt.

Assemble the burgers: place lettuce, tomato slices, pickles, and cooked patties with cheese on the buns. Top with additional house sauce if desired.