A healthy hint of cinnamon gives this chocolate cake an extra step up over the expected sheet cake. The sweet frosting is full of crunchy pecans. —Victor Clifford, San Jose, California

buttermilk

To substitute for each cup of buttermilk, use 1 Tbsp. white vinegar or lemon juice plus enough milk to measure 1 cup. Stir, then let stand 5 min. Or, use 1 cup plain yogurt or 1-3/4 teaspoon cream of tartar plus 1 cup milk.