Three-Cheese Mushroom and Spinach Calzone

I used to be a vegetarian for six years. I was a terrible vegetarian; I ate a lot of cheese, french fries and chocolate. These calzones would have fit the bill. Now, I say calzones because I made four individual calzones as opposed to one large calzones and cooked the calzones for a few minutes less. Since there are just two of us, we eat a lot of leftovers and making four individual calzones enabled us to easily package the extras in a brown bag lunch. I used the frozen pizza dough from Central Market-- it's next to the pizzas in the freezer section and is softly garlic-flavored. Next time, I may substitute mozzarella for fontina; I doubt I could taste the difference and it'll be cheaper.

4/10/11 update: tonight, substituted 1/2 lb. of hot italian sausage for the spinach and omitted the fennel seeds and red pepper flakes-- worked well. Also, learned that fontina is easier to grate if you freeze first-- 15-20 minutes.