Ingredients
1/3 cup sugar1/3 cup water1/3 cup cider vinegar1/2 large red onion, halved and thinly sliced1 jalapeno pepper, seeded and sliced6 ounces ground beef or bison1/4 pound fresh chorizo or bulk spicy pork sausage1/4 teaspoon salt1/4 teaspoon pepper2 sesame seed hamburger buns, split1/2 cup fresh baby spinach2 tablespoons peeled and grated horseradish
Preparation
In a large bowl, whisk sugar, water and vinegar together until sugar is dissolved. Add red onion and jalapeno; let stand at least 1 hour.
Combine beef and chorizo; shape into two 3/4-in.-thick patties. Sprinkle with salt and pepper. Grill burgers, covered, over medium heat until a thermometer reads 160°, 6-8 minutes on each side. Grill buns over medium heat, cut side down, until toasted, 30-60 seconds. Drain pickled vegetables. Serve burgers on buns with spinach, pickled vegetables and horseradish.
