For the calzone, knead the ingredients for the dough until it comes away from the bowl smooth (about 10 minutes). Form a ball and let rise, covered, until doubled in volume (about 30 minutes).
Finely chop the garlic and mix with the Italian herbs and the pieces of tomatoes. Season to taste with salt.
Wash the vegetables and cut them out if necessary. Cut leeks into rings, peppers into strips and mushrooms into slices.
Dice the ham, grate the cheese coarsely. Separate the egg. Preheat the oven to 200 degrees convection.
Knead the dough once more and roll out oval on a silicone mat or baking paper.
Spread the tomato sauce on one half of the dough, leaving a finger’s width of border free. On top of the tomato sauce, place all the other ingredients.
Finally, salt and sprinkle the cheese on top. Brush the edge of the oval with egg white, fold the free half of the dough over the covered half and press the edge down well.
Brush the calzone with egg yolk and bake for 30 minutes.