Melt the fat. Sweat curry and flour for about 2 minutes while stirring. Remove the pot from the heat. Peel onions and cut one into rings, the other finely diced. Clean the leek, cut into rings, wash and cook in boiling salted water for about 3 minutes.
Pour into a sieve and collect the stock. Prepare rice in boiling salted water according to instructions on the packet, season the mince with pepper and knead in the diced onion, egg and breadcrumbs. Form 8 meatballs. Heat the oil in a large pan and fry the meatballs on each side for about 4 minutes. Measure out 300 ml leek stock. Put roux back on the stove, stir in stock and milk quickly. Bring sauce to the boil and simmer for about 2 minutes. Remove the meatballs from the pan. Fry the onion rings in the frying fat until light brown, sprinkle with a little sugar.
Put roux back on the stove, stir in stock and milk quickly. Bring sauce to the boil and simmer for about 2 minutes. Remove the meatballs from the pan. Fry the onion rings in the frying fat until light brown, sprinkle with a little sugar. Stir the leek into the sauce. Arrange meatballs, onions, rice and sauce on plates