Mix the quark with the buttermilk, cinnamon and honey (or if you prefer, with half a teaspoon of stevia) and pour into a bowl and place in the refrigerator for a moment.
Cut the kumquats into 2 mm wide slices and place in a small saucepan. Add the juice of half an orange, add the sugar and the vanilla pulp, bring to the boil and simmer gently for about 5 minutes while stirring. The juice will then be a little firmer and the kumquats will be slightly transparent and soft. Then take it off the stove and let the small saucepan cool down in a cold water bath. As soon as the mixture has cooled down, pour it onto the buttermilk quark mixture and enjoy.
The portion is for one person and is very light and fruity - the kumquats are slightly sour and go well with the quark.