For the Roasted Garlic and Rosemary Spread
1 medium head garlic
2 tablespoons extra virgin olive oil, divided
1/4 teaspoon sea salt
2 tablespoons mayonnaise
1/2 teaspoon finely minced rosemary
For the Burgers
2 pounds ground American lamb
2 tablespoons minced red onion
1 teaspoon finely minced rosemary
1 1/2 teaspoons sea salt
1/2 teaspoon garlic powder
1/2 teaspoon fresh ground black pepper
To make spread, preheat oven to 425°F. Trim the woody bottom end from garlic so that all the cloves are exposed. Set a large square of foil into an ovenproof ramekin, add 1 tablespoon olive oil, sea salt, and the head of garlic trimmed side down. Wrap foil tightly around the garlic. Bake 20 – 25 minutes, or until garlic is translucent and very soft. (Be mindful as you check – the steam plume can be very hot.)
Allow garlic to cool. Squeeze cloves out of papery skins into a small bowl. Mash cloves with remaining tablespoon olive oil until smooth. Stir in mayonnaise and rosemary. Add sea salt to taste. Set in fridge to chill.
To make burgers, prepare a hot grill. Allow coals to get hot enough that you can’t hold you hand four inches above them for more than a few seconds. Bank coals to one side to create a zone of high heat and a zone of indirect heat. For a gas grill, turn to medium high 10 -15 minutes before you plan to grill.
In a medium bowl, combine ground lamb, red onion, rosemary, sea salt, garlic powder, and pepper. Knead just enough to evenly distribute onion and spices throughout. Form meat into six patties; use your thumb to make a dimple in the center of each.
Place patties over hottest part of grill. Grill 3 – 4 minutes, flip, and grill another 3 – 4 minutes. If needed, move burgers to indirect heat and cover 2 – 4 more minutes until temperature reaches 130 degrees F for medium rare or 150 degrees F for medium. Pull burgers from grill; rest 5 minutes, allowing temperature to rise another 10 degrees.
Serve burgers on toasted brioche buns with greens, sliced red onion, and prepared roasted garlic and rosemary spread