Grilled Chicken and Fruit Tacos

Name: Grilled Chicken and Fruit Tacos
Ingredients: 2 plums, quartered and pitted; 1 nectarine, quartered and pitted; 1 medium red onion, cut into 1-inch-thick rings; 1/2 red jalapeno; 2 tablespoons vegetable oil; Kosher salt; 1 1/2 pounds boneless, skinless chicken thighs (about 5 thighs); 1/2 teaspoon chipotle powder; 1/2 teaspoon dried oregano; 1/4 cup chopped fresh cilantro, plus whole sprigs for garnish; 12 corn tortillas, warmed according to package directions; 1 cup shredded romaine or green cabbage