Most british allotment growers (assuming they grow turnips at all) discard the plentiful leaves straight into the compost bin and concentrate on the roots. Turnip leaves have never, to my knowledge, been sold in british supermarkets or green grocers. In fact these leaves are highly nutritious – full of vitamins and minerals. They have similarities with spinach but are a bit peppery and somewhat coarser especially when the roots have reached any size. In Italy, where they seem to like peppery vegetables (think radiccio!), young turnip tops are often available on market stalls in Spring under the name broccoli rapa. They can be boiled or steamed but I think the nicest thing to do is a spicy chinese style stir fry with garlic, ginger, chillies and soy sauce. Older turnip tops can be used in a nourishing stew or soup, as a substitute for curly kale for example. Probably the most famous stew recipe is the Southern US dish of salt pork with turnip tops. Whether the tops are young or old strip the leaves from the coarse stalks and wash them carefully before use.
My absolutely favourite thing to do with these greens is an adaptation of Jane Grigson’s recipe for gnocchi verdi, substituting turnip greens for the spinach of the standard recipe. It is a bit of a fiddle, but definitely worth it – so here is the recipe:
Cook about 3/4 kg of turnip leaves gently in a very small amount of water until they are obviously wilted and soft. Blitz them in a food processor with 125 gm soft butter and 345 gm of ricotta cheese. Return this mixture to the pan and heat gently for about 4 minutes stirring all the time. Off the heat beat in 2 eggs, 30gm of grated parmesan cheese and at least 3 tbspns of flour (use your judgement here, more flour = heavier but easier to handle gnocchi). Spread the mixture on a flat dish and leave to chill for a while till firm(ish). Form the mixture into small balls (the gnocchi), you can use some extra flour to help with handling these balls. Heat up some lightly salted water in a wide pan till it is almost boiling and drop a batch of 5 0r 6 gnocchi into the water. Leave them to poach until they float to the top of the water, then remove with a slotted spoon . Repeat this process until all the gnocchi have been cooked. Try not to let the water boil – it can cause the gnocchi to disintegrate. Put the gnocchi in a well buttered flat dish big enough to take them in a single layer. Grate more parmesan and scatter it over them, dot with butter and place under a hot grill for a few minutes until the cheese is melted.
The gnocchi are also pretty good with a tomato sauce. They can be frozen after being poached and then unthawed before the final cooking process.