This sour plum sauce is a staple condiment in Georgia, commonly used to accompany barbecued meat or roasted potatoes. Deeply flavourful and simple to make, this is sure to become one of your favourite sauces.
Add plums to a large pot or saucepan and fill with cold water until just covered. Bring to a simmer over medium heat and cook until plums are very tender and just beginning to break down, about 20 minutes. Remove plums from water using a slotted spoon. Reserve the cooking water.
Over medium-low heat in a small saucepan heat 1 tablespoon of neutral oil until shimmering. Add onion and a generous pinch of salt and cook until softened and translucent but not browned, about 5 minutes. Reduce the heat to low and add garlic. Cook for another 30 seconds to 1 minute.
In a sieve set over the pot, add the cooked plums and press them through the sieve removing the stones and scooping any remaining flesh into the pot.
Add the cilantro and dill to the pot. Stir to combine, adding a splash of the plum cooking water, if needed, to loosen the consistency of the sauce.
Bring the sauce to a simmer and allow to cook for another five minutes. Remove from the heat and allow to cool completely before serving.