In a small bowl, whisk together the onion dip, mustard and Worcestershire sauce. Adjust the ingredients to taste. Cover and place in the icebox until ready to serve.

Place a colander over a large bowl. Add the onions to the colander. Generously sprinkle the onions with the salt and lightly toss. Let the onions set about 30 to 45 minutes to let the moisture drain.

Dump the onions out onto a clean cloth towel and press to absorb any leftover moisture. Set aside.

Form the meat into 4 equal balls.

Melt the butter in a large cast iron skillet over medium heat. Place the meat balls into the skillet. With a flat spatula or bacon/burger press, flatten the meat into thin patties.

Place a heaping amount of the onions on top of each patty. Sprinkle the tops with Kent’s seasoning or salt and pepper, to taste.

Continue cooking until you begin to see browning along the outside edge of the patties. Carefully flip the patties over so the onions are on the bottom side.

Cook for about 3 minutes then place the bottom bun, upside down, on top of the onions. Place the top bun on top of the bottom bun and leave for about 2 to 3 minutes. This will allow some of the steam and flavor to incorporate into the buns.

Remove the buns and place a slice of cheese on top of each patty. Continue cooking until the cheese melts.

Place the bottom bun on top of the burger and carefully flip the burger onto the bun and remove from the skillet. Repeat with the remaining burgers. Generously spread the French onion dip mixture on the top bun. Serve immediately.