To make the pizza dough, mix 1 tbsp. extra virgin olive oil and warm water and set aside. Mix yeast, salt and both flours together then gradually add the cup of water with oil, stirring with a large fork until it starts to come together. Kneed lightly for approximately 10 minutes and leave covered, in a warm place, until doubled in size.
Pre-heat oven to 200 degrees Celsius.
Heat olive oil in a pan and toss the Cavolo Nero for 2-3 minutes to wilt.Add wine and let the steam work through the leaves for 30 seconds, remove from heat. You should have glossy 'steamed' leaves, not watery. Tear black olives into halves, remove pips, and tear in halves again before stirring pieces through the Cavolo nero.Add marjoram leaves and Bocconcini halves (no need to cook these as they will cook in the oven).
When your pizza dough is ready, split into 4 even pieces and roll out 4 circles on a well-floured surface. They should be approx. 25cm in diameter. Place onto a baking tray, remembering that they will be folded in half so should all eventually fit on one tray.
Leaving a border of 3cm, pile an equal sized crescent shape o Cavolo Nero mixture on each round of dough, on the half closest to you. So the 'half-moon' has its round edge closest to the edge of the dough and its straight side running across the middle of the circle of dough.
Whisk egg yolk and brush along the edges of the dough before folding the empty half of the circle over the filling. Smooth the dough gently over the filling to remove excess air. Crimp the edge of the dough then fold it back on itself to seal each calzone.
Brush the top of the dough with excess egg yolk and bake for 20-25 minutes or until golden and smelling delicious.
Calzone can be served with Neapolitan or Roasted Capsicum Sauce. To make Roasted Capsicum Sauce, roast capsicum and garlic in oven at 200 degrees Celsius for 30 minutes until blistering and roasted. Remove from oven and place capsicum in plastic bag to sweat. Remove skin and seeds and cut into quarters. Blitz in a food processor with garlic, oil and vinegar. Add salt and pepper to taste.