with Caramelized Onions & Peppers
In large bowl, combine ground beef and chorizo; salt and pepper to taste. Form into 12 (5-inch) patties. Place cheese in the center of 6 patties; top with remaining patties. Press edges together, pinching to completely seal. Set aside.
In large skillet, heat oil over medium-high heat; add onion and peppers; salt and pepper to taste. Sauté until softened and caramelized (about 8-10 minutes).
Meanwhile, prepare grill to medium heat. Place burgers on grill. Grill, turning once, about 7-14 minutes or until internal temperature reaches 160°F on an instant read thermometer.
In medium bowl, combine avocado, sour cream and salsa; salt and pepper to taste. Mash to desired consistency; spread over Kaiser rolls. Top with burgers and caramelized onions and peppers.