Gently whisk the water, yeast, and sugar together. Let sit until proofed and foamy, about 10 minutes.

Add the salt, garlic powder, Italian seasoning, and olive oil and mix until combined.

Using the dough hook on your standing mixer, slowly add the flour, 1/2 cup at a time, until dough pulls away from the sides of the bowl and is no longer sticky.

Using the dough hook, knead the dough for four minutes. Let rest for three minutes. Knead for another four minutes.

Coat a bowl with olive oil, add the dough, and turn to coat. Cover the bowl with saran wrap and let rise until doubled, about one hour.

Combine all ingredients in a medium-sized saucepan over low heat. Taste and adjust as necessary.

Let cook over low heat for at least 20 minutes, up to an hour.

Preheat oven to 450 degrees. Set pizza stone in oven to get hot.

Divide dough into two equal parts. Roll out and fold over evenly.

Stuff each calzone with equal parts of the filling ingredients. Roll the edges of the calzone up to seal in ingredients.

Whisk together the egg and water. Brush the tops of the stuffed calzones. Sprinkle with parmesan and Italian seasoning.

Bake for 10-15 minutes or until tops are golden brown. Serve with pizza sauce on the side for dunking.