Wisconsin's butter burger tops a juicy beef patty with a generous pat of melting butter on a soft bun. This indulgent, protein-packed carnivore treat is a Midwest family diner classic.
Slice the yellow onion thinly and sauté in 2 tbsp of salted butter over medium-low heat for 10 minutes, stirring frequently until deeply golden and soft.
While onions cook, divide the ground beef into four 4 oz portions and shape loosely into patties, handling minimally to keep them juicy.
Preheat a cast iron skillet over medium-high heat. Season patties on both sides with kosher salt and black pepper just before cooking.
Sear burgers in the hot skillet for 3 minutes per side, pressing gently for even browning. Add 1 tbsp butter on top of each patty during the last minute of cooking and let it begin to melt.
Lightly toast brioche buns in the remaining butter in the skillet, cut side down, for 1 minute until golden.
Assemble: Top each bun base with sautéed onions, a hot butter-smothered patty, and the bun lid. Serve immediately while the butter is melting.