Ingredients

• 12 ounces prepared whole-wheat pizza dough
• 3 tablespoons mayonnaise
• 1 teaspoon white-wine vinegar
• 1 teaspoon sugar
• 1 medium clove garlic, grated
• ½ teaspoon prepared horseradish
• ¼ teaspoon ground pepper
• ¼ cup tomato sauce
• 6 ounces shredded cooked chicken breast
• ½ cup sliced red onion
• ⅓ cup shredded part-skim mozzarella cheese
• ¼ cup shredded monterey jack cheese
• ¼ cup thinly sliced scallions