How to Make It
Combine first 5 ingredients in a small bowl. Combine ketchup and next 3 ingredients (through mustard) in a small bowl; stir with a whisk.
Heat a large grill pan over medium-high heat. Rub spice mixture evenly over chicken thighs. Coat pan with cooking spray. Add chicken to pan; cook 12 minutes. Turn chicken over. Brush with half of ketchup mixture; cook 12 minutes. Turn chicken over. Brush with remaining ketchup mixture; cook 2 minutes or until a thermometer registers 165°.
Grilled summer squash: Cut 2 zucchini and 1 yellow squash lengthwise into 1/4-inch-thick slices. Brush with 2 teaspoons olive oil; sprinkle with 1/4 teaspoon salt and 1/8 teaspoon freshly ground black pepper. Grill 3 minutes on each side or until tender.