Make it veggie
Simply leave out the bacon. A great main served with a salad.
Heat oven to 180C/fan 160C/gas 4. Heat half the butter in an ovenproof frying pan. Add the bacon and cook for a few mins, then add the thyme and onions, season and cook for a further 8-10 mins until the onions are soft and golden. Scoop the onions into a bowl, leaving the buttery juices in the pan.
Off the heat, layer the sliced turnips in the pan with a scattering of fried onions, a sprinkling of cheese and some dots of butter between the layers. Season with a little salt and plenty of pepper as you go. Cover the pan with foil and bake for 1-1¼ hrs until the turnips are tender when prodded with the point of a knife. Leave the cake to relax for 5 mins. Turn it upside down onto a plate or board, then cut into wedges and serve.