Place the dough onto a baking tray along with the baking paper, cut into 4 equal strips. Spread 2/3 of the cheese over the dough, then top with the beetroot and sprinkle with the nuts.
Bake for approx. 15 mins. in the lower half of an oven preheated to 220°C.
Remove the tarte flambée and top with the remaining cheese, season.