1. STIR the flour and salt together in medium mixing bowl until evenly distributed.
2. PLACE in another, larger mixing bowl, (or the bowl of a stand mixer outfitted with the paddle attachment), the yeast, sugar, and warm water. Allow the mixture to stand until the surface begins to bubble, about 5 minutes.
3. POUR 2 tablespoons of olive oil into the yeast-water mixture.
4. ADD 1 cup of the flour and stir until well mixed. CONTINUE to add flour a cup at a time stirring after each addition until a sticky dough ball is formed.
If mixing by hand:
(5a) TURN the dough out onto a lightly floured surface. KNEAD for 5 minutes or until the dough forms an elastic character. Use a very light dusting of flour to keep the dough from sticking to the work surface; avoid adding too much flour.
If mixing with a stand mixer:
(5b) CHANGE the mixer attachment from paddle to dough hook after the last of the flour is added. An elastic dough ball will form. KNEAD the dough with the dough hook on a low speed for 3-4 minutes.
To use immediately:
(6a) PLACE the dough into a lightly oiled bowl, COVER and allow the dough to rise for 1 to 1-1/2 hours, or until doubled.
(7a) PUNCH down the dough, divide into 4 smaller, equal pieces, and continue to assemble the calzone (as above) dusting with a small amount of flour to keep things workable, and not too sticky. However, avoid adding too much flour.
If using later:
(6b) PLACE the dough into a lightly oiled bowl, COVER and place in the refrigerator for 4 hours, or up to 3 days. PUNCH the dough down if needed during chilling to keep it contained in the bowl.
(7b) REMOVE the chilled dough from the refrigerator and allow it to reach room temperature – about 1 hour. Continue as above to form the calzone.
If freezing for later use:
(6c) OIL lightly the inside of a freezer-grade plastic zipper bag. Divide dough into desired portions. PLACE in the oiled bag and place flat in the freezer.
(7c) REMOVE the frozen dough from the freezer when ready to use and allow it to defrost and rise, about 1-2 hours depending on the amount of dough and the shape of the dough. Continue as above with the calzone assembly.