Peel and chop the onion. Peel, wash and roughly dice carrot, celery and potatoes. Clean, wash and cut leek into rings.
Heat 1 tablespoon of oil in a large pot. Sauté the onion in it. Steam potatoes and vegetables briefly. Season with salt, pepper and 1 level teaspoon of sugar. Pour in 800 ml water, bring to the boil and stir in the stock.
Cover and simmer for about 25 minutes.
In the meantime, wash the parsley, shake dry, chop the leaves finely and put them aside. Halve bacon lengthwise. Wrap 1 plum with 1 bacon strip around each. Heat 1 tablespoon of oil in a frying pan. Fry the plums all around until the bacon is crispy.
Put 1 plum on each skewer.
Puree the soup with a hand blender and pass through a fine sieve into a pot. Stir in cream and bring to the boil again. Season to taste with salt and pepper. Serve and sprinkle with parsley.
Heat the remaining raspberries, puree and pass through a sieve, squeeze out the gelatine and stir into the puree. Whip the rest of the cream until stiff, add vanilla sugar and spread on the cake. Let the raspberry puree cool down a bit, put it into a small plastic bag, cut off a small corner.