Wash the potatoes and cook in boiling water for about 15 minutes. Clean and wash broccoli and cut into florets. Clean, peel and slice the carrots. Wash the meat, dab dry and dice.
Drain the potatoes, rinse with cold water and peel. Melt fat in a pot, stir in flour with a whisk and sweat for 2 minutes. Add milk and vegetable stock while stirring.
Bring to the boil and continue cooking for 1 minute. Grate cheese finely and stir into the sauce. Put potatoes, meat and vegetables in a greased casserole dish and pour the sauce over them. Cook in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 25 minutes.