Sprinkle a little cornmeal on the hot pizza stone and on the pizza peel. Roll out the dough into two 25 cm (10-inch) crusts.
In a skillet, sauté the mushrooms, onions, sundried tomatoes and garlic in the oil until the moisture from the mushrooms has evaporated. Add the spinach and sauté until wilted. Lightly season with salt and pepper.
Spread the pizza sauce on one half of the dough. Scatter the topping, salami and cheese. Moisten the perimeter with water. Fold half of the dough over the filling.
Press the dough to seal it well. Repeat with the remaining calzone. Slide the calzones on the pizza stone. Bake at the bottom of the oven for about 15 minutes.
A calzone is enough to serve two people or to satisfy one big appetite. You can also prepare four small individual calzones.