Red Onion Marmalade:
3 tablespoons butter
3 tablespoons butter
3 red onions, cut in half, then cut into 1/4-inch-wide slices
1/2 cup sugar
1 cup dry red wine
1/4 cup red wine vinegar
Kosher salt and freshly ground black pepper
1/2 cup mayonnaise
1 1/2 teaspoons fresh lemon juice
1 teaspoon Dijon mustard
2 garlic cloves, minced
Kosher salt and freshly ground black pepper
680g 85%-lean ground beef chuck
3 teaspoons olive oil
Kosher salt and freshly ground black pepper
4 whole wheat burger buns, split in half
115g Maytag blue cheese, crumbled
3 cups baby arugula
In a large sauté pan over medium-high heat, melt the butter. Add the onions and sauté until they begin to soften, about 5 minutes. Reduce the heat to low and continue cooking until onions are tender, about 12 minutes. Sprinkle sugar over the onions. Add the wine and vinegar and bring to a simmer. Simmer until the liquid evaporates and the mixture becomes slightly syrupy, about 15 minutes. Season the marmalade to taste with salt and pepper. Keep warm until serving.
In a small bowl, whisk the mayonnaise, lemon juice, mustard, and garlic to blend. Season to taste with salt and pepper.
Preheat the barbecue for medium-high heat.
Form the ground beef into four 6-ounce patties and place them on a baking sheet lined with waxed paper. Flatten the patties so they are slightly larger than the diameter of the buns. Drizzle the patties with a little oil and sprinkle with salt and pepper.
Grill the patties, oiled-side-down, until browned on the bottom, about 3 minutes. Turn the patties over and top with the cheese. Cook 3 to 4 minutes longer for medium-rare* doneness. If necessary, close the grill to help melt the cheese.
Brush the cut sides of the buns lightly with olive oil and grill, oiled-side-down, until lightly toasted with grill marks, about 1 minute. Remove the buns and burgers from the grill and allow the burgers to rest for 3 minutes.
Spread the aïoli over the bun bottoms. Mound the arugula over the bun bottoms.
Place the burgers atop the arugula. Top with a generous amount of marmalade and then the bun tops. Serve immediately. * Consuming raw or undercooked meats may increase your risk of food-borne illness, especially if you have certain medical conditions. The USDA recommends hamburgers be cooked to a minimum internal temperature of 160°F.