Tiramisu, a decadent, creamy, coffee-flavored dessert is made up of layers of rich custard separated by coffee-soaked ladyfinger cookies. Traditional recipes call for dusting the top with a layer of unsweetened cocoa, but some pastry chefs go one step further and add a layer of ganache. When you're trying to make tiramisu at home, you might have an issue with watery cream, which turns the whole dessert into a soggy mess.
Cut Down on the Coffee
If your cream is only slightly too thin, the ladyfingers should soak up the excess liquid. If the ladyfingers are already saturated with coffee, they will not be able to absorb any moisture from the cream. Instead, they will slowly release the coffee into the cream, making it even more watery. To fix this problem, dip the ladyfingers in the coffee for just a few seconds. If you want a stronger coffee flavor, mix instant espresso into the unsweetened cocoa that you'll dust on top.
If, as you are assembling your tiramisu, the cream seems a little too watery, keep in mind that it will firm up as it sets. Most tiramisu recipes call for allowing the assembled dessert to chill in the refrigerator for several hours or overnight. This will give the ladyfingers time to absorb some of the moisture. Chilling also helps the fat in the cream solidify, giving the cream a firmer texture.
Secret Ingredient: Gelatin
The cream for tiramisu is really a basic custard. Adding gelatin to the mascarpone and cream mixture will absorb excess moisture in the cream and produce a firmer custard when you fold in the whipped egg yolks. To use gelatin successfully, be sure to "bloom" the gelatin for a few minutes before adding it to the cream. Warm a small amount of the cream and sprinkle one envelope of powdered gelatin over it. Let this sit until the gelatin is soft, then mix the gelatin and cream into the remaining cream and proceed with your tiramisu recipe. Gelatin-thickened custards must chill to achieve their final firmness, which works well with a tiramisu recipe.
Secret Ingredient: Starch
If you have had problems before with watery cream, consider adding 1 tablespoon of cornstarch per 1 cup of heavy cream just before you whip it. The starch will absorb some of the liquid in the cream, making a firmer, more stable whipped cream. This will provide additional structure when you fold in the mascarpone cream and whipped egg yolks, preventing the final cream from becoming watery.