An Olive magazine Dec 2015 recipe. We had this on Christmas day.

olive oil
butter
1 onion, finely sliced
1 swede, peeled and cut into batons
500g sweet potato, peeled and cut into batons
200g kale, washed thoroughly and finely chopped
200ml whipping cream
100ml milk
nutmeg for grating
1 bay leaf
Heat the oven to Gas 4/180ÂșC. Heat a little oil and a knob of butter and gently fry the onion until iit is very tender but not coloured. Add the swede and sweet potato, mix really well, cook gently for about 5 minutes then season and add the kale. Mix and then tip into a large buttered baking dish about 1½ litres in capacity.
Bring the milk and cream to a simmer and pour over the veg. Grate over some nutmeg and add the bay leaf.
Bake for 45 minutes or until the veg are tender and the top is browned.