Yogurt-Basil Chicken Kabobs

This is a Martha Stewart Recipe that is one of my favorite summer specialties.

Ingredients
Makes about 20
1 cup plain yogurt
1 cup packed fresh basil leaves, chopped
1/4 cup chopped red onion
1/2 teaspoon curry powder
Salt and freshly ground pepper
2 pounds boneless skinless chicken thighs, trimmed of excess fat and cut into 1 1/2-inch pieces
1 yellow bell pepper, stemmed, seeded, and cut into 1-inch squares
1 large zucchini, quartered lengthwise, then cut into 1-inch pieces
1 pint (12 ounces) large cherry tomatoes
1 tablespoon olive oil
Directions
Pulse yogurt, basil, and onion in a food processor several times. Transfer yogurt mixture to a nonreactive bowl. Stir in curry powder and 1/4 teaspoon salt. Reserve 1/2 cup of the yogurt mixture for dipping.
Add chicken to bowl with remaining yogurt mixture; toss to coat. Cover, and refrigerate at least 45 minutes (or up to 6 hours). Meanwhile, soak twenty 8-inch skewers in water for 30 minutes.
Preheat grill to medium. Toss together bell pepper, zucchini, tomatoes, and oil in a medium bowl. Season with a pinch each of salt and pepper. Thread chicken and vegetables onto skewers, and transfer to a parchment-lined baking sheet.
Grill kabobs, turning occasionally, until chicken is cooked through and vegetables are charred, about 14 minutes. Serve with reserved yogurt mixture for dipping.