Combine softened butter, red onion, garlic, parsley, Worcestershire sauce, Dijon mustard, lemon juice, lemon zest, paprika, chili flakes, and chives in a mixing bowl. Season with salt and pepper. Mix thoroughly.
Divide the ground beef into 8 equal portions, about 3 ounces each. Use a kitchen scale for accuracy.
Shape each portion into a thin patty. Season both sides of each patty with salt and black pepper.
Heat a large skillet over medium-high heat. Add the patties and cook for 3-4 minutes per side until cooked through. Adjust cooking time as needed.
Toast the cut sides of the hamburger buns until lightly golden. Spread the softened Cowboy Butter generously on the top buns.
During the 30 seconds of cooking, place a slice of cheese on top of each patty to melt. Remove patties from skillet and allow to drain on a paper towel lined plate.
Spread ketchup and mustard on the bottom buns. Add shredded lettuce, red onion slices, and pickle chips to the bottom buns.
Place two cheeseburger patties on the bottom bun. Cover with the top bun and serve imm