2 tablespoons plus 1/2 cup chopped fresh cilantro, divided
3 tablespoons lime juice, divided
3/4 teaspoon salt, divided
1/4 teaspoon crushed red pepper flakes
1/8 teaspoon chili powder
4 boneless skinless chicken breast halves (6 ounces each)
3 cups fresh cauliflower florets (about 1/2 small cauliflower)
1 tablespoon canola oil
1 small red onion, finely chopped
Toasted sweetened shredded coconut or lime wedges, optional
For marinade, place 1 can pineapple, yogurt, 2 tablespoons each cilantro and lime juice, 1/4 teaspoon salt, pepper flakes and chili powder in a food processor; process until blended. In a large bowl, toss chicken with marinade; refrigerate, covered, 1-3 hours.
In a clean food processor, pulse cauliflower until it resembles rice (do not overprocess). In a large skillet, heat oil over medium-high heat; saute onion until lightly browned, 3-5 minutes. Add cauliflower; cook and stir until lightly browned, 5-7 minutes. Stir in 1 can pineapple and the remaining lime juice and salt; cook, covered, over medium heat until cauliflower is tender, 3-5 minutes. Stir in remaining cilantro. Keep warm.
Preheat grill or broiler. Drain chicken, discarding marinade. Place chicken on an oiled grill rack over medium heat or in a greased foil-lined 15x10x1-in. pan. Grill, covered, or broil 4 in. from heat until a thermometer reads 165°, 4-6 minutes per side. Let stand 5 minutes before slicing.
To serve, divide cauliflower mixture among 4 bowls. Top with chicken, remaining 1 can pineapple and, if desired, coconut and lime wedges.