Ginger Mashed Veggies Recipe

2 medium sweet potatoes, peeled and cut into 1-inch cubes 4 small carrots, cut into 1-inch chunks 2 medium parsnips, peeled and cut into 1-inch chunks 1/4 cup half-and-half cream 2 tablespoons reduced-fat butter 2 tablespoons reduced-fat sour cream 2 tablespoons molasses 1 teaspoon minced fresh gingerroot 3/4 teaspoon salt 1/2 teaspoon pepper