Heat 2 tbsp olive oil in a pan, and sautee the spinach and onions until wilted. Add half the wine and simmer until the liquid evaporates. Add the breadcrumbs and sautee a little more.
Leave to cool, then add the mustard and mix. Beat the turkey breast fillets to flatten them, then add salt and pepper. Add the spinach misture onto the turkey breast fillets, then add the grated cheese, roll and tie with string. Add salt and pepper.
Heat the rest of the olive oil and fry the turkey fillets very well on all sides. Place in a baking tin and add the rest of the wine and 1 cup warm water, in which you have dissolved 1 vegetable stock cube. Bake at 200 °C for 1 hour and 15 minutes, covered with tin foil. Serve the rolls slices, with pasta or rice.