Although calzone sounds like a potentially fussy dish, you can actually make this in about an hour, start to finish. The simple filling comes together quickly while the dough rises, and then assembly is easy since everything goes together in one big calzone. (You could also make smaller individual calzones if you prefer, and if you want to spend a little extra time.)
The filling is delicious, and I highly recommend seeking out fresh ricotta cheese - I used the cheaper sort, and while the calzone was still tasty, I think it would have been even better with higher quality cheese. I used both spinach and chard because it was what I had on hand, but you could use just one if you prefer. This filling has a high proportion of greens to cheese, which I really liked, but you can adjust this to your preference and reduce the amount of greens if you like. I used red chard, which was delicious but did dye my filling pink, so use red or rainbow chard at your own risk!
The most unusual ingredient in this filling was a minced chipotle in adobo. The amount included here doesn't make the calzone spicy, but adds a terrific smoky flavor. Of course, you can use more if you'd like a spicier dish. Don't skip the tomato sauce to serve alongside the calzone - the filling isn't very moist, which is great because the calzone doesn't get soggy. But, the dish overall would be too dry without a sauce on the side.
Spinach-Chard Calzone (adapted from Secrets of the Best Chefs: Recipes, Techniques, and Tricks from America's Greatest Cooks)
4 ounces stemmed Swiss chard leaves
4 ounces baby spinach leaves
1 cup ricotta cheese
1 small ball fresh mozzarella, chopped
1 chipotle in adobo chile, minced
1 recipe quickie pizza dough, using 1 cup all purpose flour and 1/2 cup whole wheat flour
Hot tomato sauce, to serve
1. Preheat the oven to 400 degrees and line a large baking sheet with parchment or foil.
2. Rinse the greens well. Heat a large non-stick skillet over medium heat. Add the chard leaves, with some water still clinging to the leaves, and stir occasionally until they begin to wilt. Add the spinach leaves, and continue to stir until all the greens are wilted. (Add more water or reduce heat if it looks like the greens are starting to brown instead of wilt.)
3. Drain the greens, let cool slightly, and then squeeze out as much moisture as possible. Chop the greens.
4. Add the greens to a bowl with the ricotta, mozzarella, egg, and chipotle chile. Mix to combine. Add salt to taste.
5. Stretch out the dough into a large oval. Add the filling to one side, leaving a border around the edges. Fold over the part of the dough that is not covered with filling, and pinch the edges shut. Slash the top to create steam vents.
6. Bake about 25 minutes, until the top is golden brown. Let cool slightly, and then slice and serve with tomato sauce.