Peel garlic and dice finely. Wash the marjoram and dab dry. Put 4 stems aside for garnishing, remove the rest of the leaves. Wash the savory, pluck from the stalks and chop finely.
Heat the oil in a pot. Sauté the garlic in it. Add the lentils, marjoram, savory and tomato paste and sauté briefly. Add stock, bring to the boil. Simmer at low heat, stirring frequently, for about 15 minutes.
Clean and wash the celery and cut into fine rings. Add celery 5 minutes before the end of cooking time. Wash, clean and halve the cherry tomatoes. Add to the soup. Remove the savory. Season to taste with salt, pepper and sugar.
Mix horseradish and crème fraîche. Arrange soup in bowls, garnish with marjoram set aside. Add dip.