Farmers’ Market Burgers with Grilled Red Onion Relish and Peppered Tomato Mayonnaise
Peppered Tomato Mayonnaise
- 1/2 cup mayonnaise
- 4 teaspoons high quality tomato paste
- 2 teaspoons Dijon mustard
- 3/4 teaspoon freshly ground black pepper
Grilled Red Onion Relish
- 2 tablespoons high quality olive oil
- 2 red onions, cut in half and sliced 1/4 inch think
- 2 red bell peppers
- 1 ear of corn, in the husk
- 10 ounces grape tomatoes, cut in half and each half cut into thirds
- 2 tablespoons coarsley chopped fresh parsley
- 1 teaspoon salt
- 1 tablespoon high-quality olive oil
- 1/2 cup grated carrots
- 1 cup diced cremini mushrooms
- 2 pounds ground turkey
- 1/2 cup diced grilled red onion (from making the relish)
- 1 extra-large egg, lightly beaten
- 1/4 cup finely ground fresh bread crumbs, made from high-quality bread
- 1/4 cup Dijon mustard
- 1 large clove garlic, minced or grated
- 2 teaspoons coarsely ground sea salt
- 1 teaspoon freshly ground black pepper
- Vegetable oil, for brushing on the grill rack
- 6 high-quality, whole-grain hamburger buns, split
- 6 slices aged sharp white Cheddar cheese
- 3 ounces prewashed baby spinach
Prepare a medium-hot fire in a charcoal grill with a cover, or preheat a gas grill to medium-high.
To make the mayonnaise, combine all the ingredients in a bowl and whisk to blend well. Cover and refrigerate until assembling the burgers.
To make the relish, heat the oil in a fireproof skillet on the grill until hot but not smoking. Add the onion and cook until soft and caramelized. Remove from the grill and allow to cool. Place the bell peppers and corn on the grill and cook until charred on each side. Remove the peppers to a bowl, cover with plastic wrap, and set aside for 10 minutes. Let the corn cool until you can handle it easily. Peel the peppers over a clean bowl, catching any juices. Seed the peppers, cut into a rough 1/4-inch dice, and transfer to the bowl with their juices. Husk and silk the corn, slice the kernels from the cob, and add them to the peppers. Chop the onions into a rough dice, reserving 1/2 cup for the patties, and add the remaining to the pepper and corn mixture. Add the tomatoes, parsley, and salt and toss. Cover and refrigerate until assembling the burgers.
To make the patties, heat the oil in a fireproof skillet on the grill until hot but not smoking. Add the carrots and mushrooms and sauté until soft, 5 to 7 minutes. Remove from the heat and let cool. Place the turkey in a large bowl. Add the onion, egg, bread crumbs, mustard, garlic, salt, pepper, and the sautéed vegetables. Using a fork and taking care not to compact the meat, mix until the ingredients are thoroughly incorporated and evenly distributed throughout. Form into 6 equal patties to fit the buns. Cover and refrigerate until ready to grill.
Brush the grill rack with vegetable oil. Place the patties on the rack, cover, and cook, turning once, until the juices run clear, 5 to 7 minutes on each side. During the last 2 minutes of cooking, place the buns, cut side down, on the outer edge of the grill rack to toast lightly. During the last minute of grilling, top each patty with 1 slice of the cheese.
To assemble the burgers, spread a generous amount of the mayonnaise over the cut sides of the buns. On each bun bottom, place equal portions of the spinach, a patty, and a generous portion of the relish. Add the bun tops and serve.