This crispy pizza turnover, whose name means "trouser leg" (for its shape), is a specialty of Naples—san marzano territory.
FOR THE DOUGH:
1 7-gram packet active dry yeast
1 1/2 cups all-purpose flour
1 1/2 cups cake flour
1 tsp. salt
Extra-virgin olive oil
1/2 cup cornmeal
FOR THE FILLING:
1/2 lb. fresh mozzarella, sliced into 8 pieces
16 oil-packed anchovy filets
1 14-oz. can peeled whole san marzano
tomatoes, drained and chopped
2 tsp. fresh oregano leaves
1. Dissolve yeast in 1/4 cup lukewarm water in a large bowl and set aside until foamy, about 10 minutes. Combine flours and salt in a bowl. Add 1 cup flour mixture to yeast. Stir with a wooden spoon. Add 1/2 cup water, then 1 cup flour. Mix well, then work in remaining 1 cup flour. Gradually add another 1/4 cup water to make a soft, moist dough.
2. Turn out dough onto a lightly floured surface and knead until smooth, 10–12 minutes. Divide dough into 4 balls. Lightly coat the inside of 4 small bowls with olive oil. Place 1 ball of dough in each bowl. Cover with damp cloths and set aside to rise until dough doubles in bulk, 2 1/2–3 hours.
3. Place pizza stone in oven and preheat oven to 450°. On a floured work surface, stretch 1 ball of dough into a thin 9'' circle. Place 2 slices mozzarella, 4 anchovy filets, and 2–3 tbsp. tomatoes on one side of 1 circle of dough. Sprinkle with oregano, fold dough over, and pinch to seal. Repeat process to make a total of 4 calzoni.
4. Sprinkle cornmeal on pizza stone, place calzoni on top, and brush with a little oil. Bake until golden, about 15 minutes.