Peel the carrots and, depending on the size you want, grate or chop them in the Thermomix.
Put the carrots in a saucepan, cover with the water and cook for about 15 minutes until they are soft. Then strain the water. Add the sugar to the carrots and simmer for 30 minutes. The carrots should now be thickened. If the carrot syrup is too runny, stir in 3 tablespoons of preserving sugar if necessary and simmer for another 10 minutes. Finally stir in the vanilla sugar and lemon juice.