- 2 pounds ground sirloin or chuck
- 1/2 cup Worcestershire sauce
- 2 tablespoons grainy Dijon mustard
- 2 tablespoons prepared horseradish
- Kosher salt and coarse black pepper
- Melted butter, for basting
- 12 ounces (3/4 pound) sliced sharp white cheddar
- 6 burger rolls, toasted
- Green leaf or butter lettuce leaves
- Sliced beefsteak tomatoes
- 1 Vidalia or other mild sweet onion, thinly sliced
For the Chunky Blue Cheese Aioli
- 1 cup homemade* or store-bought mayo
- 6 ounces crumbled blue cheese or smoked blue cheese crumbles
- 2 tablespoons finely chopped flat-leaf parsley
- 1 tablespoon grainy Dijon mustard
- 1 large clove garlic, grated or pasted
* For Homemade Mayo
- 1 organic egg yolk
- 1 teaspoon Dijon mustard
- 2 tablespoons fresh lemon juice
- 2/3 cup grapeseed oil
- Sea salt
In a large bowl, combine the beef, Worcestershire, Dijon and horseradish; season with salt and pepper. Shape into 6 patties. Heat a griddle or cast-iron skillet over medium-high. Cook patties, turning occasionally and basting with melted butter, about 8 minutes for medium-rare. Top with slices of cheddar and cover for the last minute or two of cooking until the cheese melts.
For the mayo, in a medium bowl, whisk the egg yolk, Dijon and lemon juice; then, continuing to whisk, slowly stream in the oil, letting it pour down the sides of the bowl. Season with sea salt.
For the aioli, in a medium bowl, mix the mayo, blue cheese, parsley, Dijon and garlic.
Divide the cheeseburgers among the roll bottoms; spread the aioli on the roll tops. Top the burgers with lettuce, tomato, onion and the roll tops.