Grilled chicken with peanut sauce

1 garlic clove, minced
1/4 cup peanut butter (any kind)
2 tbsp sugar
1/4 tsp red chile flakes
2 tbsp reduced-sodium soy sauce
4 boned, skinned chicken breast halves (about 2 lbs)
1 tbsp vegetable oil

1. Prepare a grill for high heat (450 to 550degrees). In a small saucepan over medium heat, cook garlic and peanut butter together until simmering, about 4 minutes. Whisk in sugar, chile flakes, soy sauce, and 2/3 cup water. Reduce heat and simmer, stirring occasionally, until starting to thicken, about 10 minutes.
2. Meanwhile, rub chicken with oil and grill until golden brown and almost cooked through, turning once, about 6 minutes total. Brush top of each chicken piece with 1 tbsp peanut sauce and cook just until sauce starts to caramelize, about 2 minutes. Serve with steamed vegetables and remaining sauce on the side.