Preheat the oven to 160°C/Fan 140°C/Gas 3. Heat 1 tablespoon of the oil in a casserole over a gentle heat, add the onions and carrots, cover with a lid and sweat for 10 minutes.
Heat 1 tablespoon of the oil in a frying pan until almost smoking. Sear the beef on all sides, then add to the casserole. Sprinkle the flour over the meat and cook for 1–2 minutes. Add the wine, stock and tomatoes to the frying pan, bring to the boil and then add to the
casserole. Season the casserole with salt and pepper, cover and cook in the oven for 2 ½ –3 hours, depending on the cut of meat.
Meanwhile, heat the remaining oil in a pan over a high heat, saute the mushrooms and add to the casserole with the parsley about 15 minutes before the end of cooking.
To make the polenta, pour 1.7 litres water into a deep, heavy-bottomed saucepan and bring to the boil, then add the salt and sprinkle in the polenta very slowly, letting it slip gradually through your fingers, whisking all the time (this should take 2–3 minutes). Bring to the boil and when it starts to erupt like a volcano, reduce the heat to the absolute minimum.
Cook for about 40 minutes, stirring regularly. I use a whisk at the beginning but as soon as the polenta comes to the boil I change to a flat-bottomed wooden spoon. The polenta is cooked when it is very thick but not solid and comes away from the sides of the pan as you stir.
As soon as the polenta is cooked, stir in the butter, Parmesan and lots of freshly ground pepper. Taste and add a little more salt if necessary. It should be soft and flowing; if it is a little too stiff, add some boiling water.
Just before you’re ready to serve, make the gremolata by mixing all the ingredients together in a small bowl.
Serve the stew topped with the gremolata, if using, with the polenta and a good green salad alongside.