Wash the potatoes thoroughly and cook in plenty of boiling water for 15-20 minutes. Quench potatoes, peel and halve. Peel, wash and halve carrots and cut into pieces.
Cook in the boiling broth for about 15 minutes. Peel and finely dice the onion. Pour the carrots onto a sieve and collect the stock. Heat the fat in a saucepan and sauté the onion. Add flour and sauté.
Add the stock while stirring and bring to the boil. Add cream and cheese to the stock. Season to taste with salt and pepper. Cut ham into strips. Add potatoes, carrots and ham to the sauce. Heat up again.
Place the potato ragout in a bowl and sprinkle with chive rolls.