Making runny fruit filling

It's not just disappointing to cut into a steaming hot, fruit-filled pierogi and have juice squirt out; it's also a little dangerous. Berries, apples, and other fruits contain a significant amount of water, which is released when the fruits are cooked. As a result, if you're making fruit-filled pierogi, you should take precautions to prevent the filling from becoming runny.

There are a few things you can do, just like with runny pie filling, to keep your pierogi fruit filling from releasing too much liquid. The first step is to ensure that you have sufficiently precooked your fruit to release the majority of the moisture. Following that, you can use any of a variety of thickening agents. Thickeners such as corn starch, gelatin, flour, or tapioca, according to Science of Cooking, will increase the viscosity of a liquid without significantly changing its flavor. Cornstarch is commonly used by cooks and bakers because it works quickly and produces a pleasing translucent sauce. In fact, Martha Stewart prefers cornstarch as a thickener.