Wash the meat, dab dry and rub with salt and pepper. Spread with cheese and cover with bacon. Roll up meat firmly and tie up with kitchen string. Peel and quarter onions. Put meat and onions on a fat pan and fry in the preheated oven (electric cooker: 175 °C/ gas: level 2) for approx. 1 3/4 hours.
After half of the frying time, deglaze with broth. In the meantime, clean and wash the carrots. Clean, wash and cut kohlrabi into sticks. Clean, wash and slice the zucchini. Peel and slice garlic. Cook carrots and kohlrabi separately in boiling salted water for about 15 minutes. Heat oil in a pan, fry garlic and zucchini for about 5 minutes while turning. Stir in sour cream and season to taste with salt and pepper. Wash parsley, dab dry and chop finely. Take the roast out of the oven, cover and let it rest for about 5 minutes.
Heat oil in a pan, fry garlic and zucchini for about 5 minutes while turning. Stir in sour cream and season to taste with salt and pepper. Wash parsley, dab dry and chop finely. Take the roast out of the oven, cover and let it rest for about 5 minutes. In the meantime, pour roast stock through a sieve and bring to the boil, stir in sauce thickener, bring to the boil again and season with salt and pepper. Arrange roast, zucchini, carrots as desired with grated lemon peel and kohlrabi sprinkled with parsley on a plate. Add sauce extra