The effect which this enchantment imparts makes any food item regenerate 100% more vitality when consumed. This is achieved by doubling the duration over which food items heal, so while the total amount of restored vitality is doubled, the rate at which it is restored remains the same.
The in-game crafting menu shows that two pyerog runestones are needed to craft this enchantment, when in truth only one is required.
The duration bonus also combines with the Gourmet ability. While having equipped a sword enchanted with Dumplings, every food item eaten will restore health for 40 minutes.
The crafting requirements is a joke at dumplings itself, with pyerog being a reference to pierogi dumplings and tvarog (Polish: twaróg) being a reference to quark cheese. The required ingredients is further written as "pyerog, tvarog, pyerog" referring to the most common kind of pierogi, pierogi ruskie, which are made with quark cheese stuffing enclosed between two layers of dough.