Name: Millstones Millstone Cheeseburger Recipe
Cook time: 1 h
Total time: 1 h
Yield: 2 servings
Cuisine: American
Ingredients: 1 lb ground beef (80/20); 1 tsp fine salt; 0.5 tsp freshly ground black pepper; 1 tbs vegetable oil (for griddle/skillet); 0.25 cups mayonnaise; 1 tsp yellow mustard; 1 tsp ketchup; 1 tbs finely diced dill pickle (or relish); 0.5 tsp Worcestershire sauce; 0.25 tsp garlic powder; 0.25 tsp onion powder; 0.5 tsp hot sauce (optional); 1 large yellow onion; 1 tbs unsalted butter; 1 tsp olive oil; 0.25 tsp fine salt; 0.5 tsp brown sugar (optional, helps color); 0.5 tsp apple cider vinegar (optional, to finish); 2 slices American cheese slices; 3 slices house-cured bacon or smoked bacon; 1 each house roll (or brioche roll), split; 0.5 tbs butter (for toasting buns); 2 leaves leaf lettuce; 2 slices tomato; 0.25 tsp kosher salt; 0.25 tsp freshly ground black pepper

Method

Caramelized Onions

slice onions

Peel the large yellow onion and slice it thinly (about 1/8-inch).

Heat a medium skillet over medium-low heat. Add the butter and olive oil and let the butter melt and foam.

Add the sliced onions and sprinkle with 1/4 tsp fine salt. Stir to coat, then spread the onions into an even layer. Cook slowly, stirring every 2–4 minutes so they brown evenly. Reduce heat if they start to burn.

After 15–20 minutes they will be deep golden and soft. If desired, sprinkle 1/2 tsp brown sugar and stir to help caramelization. Continue cooking another 5–10 minutes until fully caramelized (total 20–30 minutes).

Finish with 1/2 tsp apple cider vinegar to brighten the flavor, stir, then remove from heat and set aside.

Smash Sauce

In a small bowl combine 1/4 cup mayonnaise, 1 tsp yellow mustard, 1 tsp ketchup, 1 tbsp finely diced dill pickle or relish, 1/2 tsp Worcestershire sauce, 1/4 tsp garlic powder, 1/4 tsp onion powder, and 1/2 tsp hot sauce if using.

Stir until smooth. Taste and adjust salt or acid if needed. Refrigerate until ready to assemble.

Bacon & Buns

Cook the bacon in a skillet over medium heat until crisp, about 6–8 minutes, turning as needed. Transfer to a paper towel-lined plate to drain.

Butter the cut sides of the house roll with 1/2 tbsp butter. Toast cut-side down on the skillet (or griddle) over medium heat until golden, about 1–2 minutes. Remove and keep warm.

Burger Patties & Assembly

Divide the 1 lb ground beef into two equal portions (about 8 oz each) and loosely form into ball shapes. Do not overwork the meat; keep them slightly loose so they smash properly.

Heat a large cast-iron skillet or flat griddle over medium-high until very hot. Add 1 tbsp vegetable oil and spread to coat. Place one beef ball on the hot surface and immediately press down firmly with a metal spatula or a weighted press to create a thin patty (~1/4-inch thick). Repeat with the second ball, leaving space between patties.

Sprinkle each smashed patty with a pinch of kosher salt and freshly ground black pepper. Cook without disturbing for 2–3 minutes until the edges are deeply browned and crisp.

Flip the patties, quickly place a slice of American cheese on each patty, and cook for another 30–60 seconds until cheese melts and the patty is cooked through. Remove patties to a plate.

Season tomato slices lightly with a pinch of kosher salt and pepper.

To assemble: spread about 1–2 tbsp of smash sauce on the bottom half of the toasted roll. Place lettuce leaf(s) on the sauce, then add the cheese-topped smashed patties. Top patties with 2–3 slices of crispy bacon and a generous spoonful (about 2–3 tbsp) of caramelized onions. Add tomato slices on top of onions if you prefer them above; otherwise place tomato on lettuce before patties. Spread a little smash sauce on the top roll if desired, then close the burger.

Serve immediately while hot. Cut in half if desired.