Varenyky with Potato & Frizzled Onions

Ingredients

• 3 cups all-purpose flour, plus more for rolling
• 1 cup warm water
• 1 egg
• 2 tbsp sunflower oil
• 1½ lb starchy potatoes, peeled and cubed
• 5 oz farmer cheese or dry cottage cheese
• 3 large onions, sliced thin
• 5 tbsp butter
• ½ cup sour cream, for serving
• Salt and white pepper

Method

1. Stir the flour, warm water, egg, oil, and a big pinch of salt into a shaggy dough, then knead 8 minutes until it springs back when poked. Cover and rest 30 minutes — this is not optional, it is what makes the dough roll thin without fighting you.
2. Boil the potatoes in salted water until a knife slides through, 15 minutes. Drain very dry, mash with the farmer cheese, 1 tbsp butter, salt, and white pepper. Cool to warm.
3. Melt the remaining butter in a wide skillet over medium-low and cook the onions, stirring now and then, until deep gold and sweet, 20–25 minutes. Stir a third of them into the filling.
4. Roll the dough ⅛ inch thick and cut 3-inch rounds. Spoon a walnut of filling into each, fold, and pinch the seam firmly — a dry seam holds, a wet one leaks.
5. Simmer the varenyky in well-salted water in batches. They sink, then float; give them 2 more minutes after they surface, then lift out with a spider.
6. Toss the hot dumplings in the buttery onions and serve with cold sour cream. Any that survive the night fry beautifully in butter for breakfast.