Clean the Brussels sprouts and cut large heads in half. Peel, wash and slice carrots diagonally. Peel, wash and halve or quarter potatoes. Cook potatoes and Brussels sprouts in a pot of boiling salted water for about 10 minutes.
After 5 minutes add the carrot slices. Drain the vegetables. Peel onion and cut into cubes. Heat the fat in a pot. Sauté onion cubes and curry and dust with flour. Fill up with cream and vegetable stock.
Season with salt and pepper and place in an ovenproof dish with the vegetables. Crumble the feta cheese and spread it on top. Cook in the preheated oven (electric cooker: 250 °C/ convection oven: 225 °C/ gas: level 5) for 10-15 minutes.