Pineapple Upside-Down Cake

INGREDIENTS

• 7 slices canned unsweetened pineapple (20-ounce can)
• 3 tablespoons unsalted butter
• ¾ cup packed light brown sugar
• 19 maraschino cherries
• 2 large eggs
• 2 tablespoons buttermilk
• ½ teaspoon vanilla
• 1 cup all-purpose flour
• ¾ cup granulated sugar
• ¾ teaspoon baking powder
• ¼ teaspoon baking soda
• ¼ teaspoon salt
• 6 tablespoons (¾ stick) unsalted butter, softened
• 6 tablespoons buttermilk