Dough
Place the flour in a bowl and create a well in the centre. Stir the yeast and wine into the well to create a thin paste, dust with a little flour. Set aside until the paste begins to froth (approx. 30 mins.). Add the rosemary, salt, oil and mineral water to the flour, mix and knead into a soft, smooth dough. Cover and leave to rise at room temperature for approx. 1 hr. until doubled in size.
Filling
Fry the Mortadella, onion and garlic, without any oil, in a non-stick frying pan for approx. 2 mins. Add the tomatoes, cook for a further 5 mins., season. Allow the mixture to cool. Cover and set aside the olives and capers.
To shape, brush the ring-shaped cake mould with olive oil and sprinkle with the rosemary. On a lightly floured surface, roll the dough out into a rectangle (approx. 40 x 48 cm). Spread the filling over the dough. Scatter the reserved olives and capers on top. Roll the dough up from the long edge, cut in half lengthwise. Individually twist both pieces of dough into spirals from the ends to the middle, place on top of each other in the prepared cake mould and leave to rise for approx. 30 mins.
Bake for approx. 25 mins. in the lower half of an oven preheated to 200°C. Remove and turn out onto a baking tray. Return to the oven and bake for approx. 10 mins.