1. Prepare Chimichurri Topping. Set aside. In a large bowl, combine beef, pork, chili powder, onion powder, cumin, and salt. Mix well. Shape into six 1/2-inch-thick patties.

2. For a charcoal grill, grill patties on the rack of an uncovered grill for 10 to 13 minutes or until an instant-read thermometer inserted into side of each patty registers 160°F, turning once halfway through grilling. (For a gas grill, preheat grill. Reduce heat to medium. Place patties on grill rack over heat. Cover and grill as above.)

3. Place each grilled patty on top of two of the pita quarters. Top with roasted peppers and Chimichurri Topping.

Chimichurri Topping: In a small bowl, combine 1/2 cup finely snipped fresh flat-leaf parsley; 1/2 cup finely snipped fresh cilantro; 2 tablespoons red wine vinegar; 1 tablespoon olive oil; 2 cloves garlic, minced; 1/4 teaspoon salt; 1/4 teaspoon ground black pepper; and 1/8 teaspoon cayenne pepper.