Kohlrabi and Potatoes with Sour Cream and Dill

2 tbsp butter 
3 cups kohlrabi, peeled and cut into rough chunks
2 potatoes cut into rough chunks
1/4 tsp paprika
1 cup vegetable stock
½ cup sour cream or crème fraîche
1 bunch of fresh dill, roughly chopped

Heat the butter in a pan over a medium heat and add the kohlrabi, paprika, potato and a little salt. Stir, lower the heat, cover and leave for 5 minutes or so.
Add the stock, bring to a gentle simmer and cover again. Cook for 25-30 minutes or until the vegetables are soft enough to cut with a spoon. The stock should have reduced quite a bit by then but don’t worry if it hasn’t.
Raise the heat for about 5 minutes. Stir in the soured cream or crème fraîche and remove from the heat. Add salt as needed, then fold in the dill to serve.