Heat a tablespoon of oil in a frying pan, ensuring that the pan is very hot, add the beef fillet and sear for 30 seconds to a minute on each side and remove from the pan.
Using the same pan add another tablespoon of oil, along with the mushrooms, thyme leaves and the butter, cook, stirring occasionally. When cooked, season well.
Wilt the spinach in a sauce pan and drain, then place it in an oven-ready dish, making a layer.
Lay the beef on the spinach and top each steak with the mushrooms and a slice of Dolcelatte.
Cut the parsnips into batons and coat with the remaining tablespoon of oil, season and roast at 160°c in the oven for 20-30 minutes till soft and golden, remove from the oven an add the honey to coat the parsnips.
This can all be prepared in advance to this stage.
When ready to serve, pre-heat the oven to 180°C.
Cook the beef for 8-10 minutes in the oven, allowing the cheese to melt.
Warm the beef jus in a pan and reheat the parsnips in the oven for 10 minutes.