Cheesecakes do often sink in the middle or get cracks on top. While unsightly, this does not detract from their amazing flavor. It's no coincidence that so many recipes call for a topping, such as a baked topping of sour cream or a fruit topping. These cheesecakes never crack when I make them (as long as the ingredients are at room temperature). But they do sink a little in the middle, which is actually perfect for the chocolate topping.