Wash and peel the cucumbers, cut them in half lengthwise and remove the seeds. Cut the cucumbers into slices. Peel and chop onion. Heat 1 tablespoon of oil in a pan. Fry the onion and minced meat for about 5 minutes, turning occasionally.
Season with salt and pepper. Prepare rice in boiling salted water according to package instructions. Remove minced meat from the pan. Heat 1 tablespoon of oil in a frying pan. Fry the cucumbers for 3-5 minutes. Add minced meat.
Add vegetable stock, bring to the boil and cook everything for 7-8 minutes over medium heat. Wash the dill, dab dry, pluck flags from the stems. Put something aside for garnishing. Coarsely chop the remaining flags.
Stir the sour cream and dill under the cucumber pan. Bring to the boil again briefly and season to taste with mustard, salt, pepper and a little sugar. If necessary, thicken with a little sauce thickener. Garnish the cucumber pan with dill and add the rice.