For the Pizza Dough: Fit mixer with dough hook. Add flour, salt, sugar and yeast to the mixer bowl. Turn mixer on low, add 2 tablespoons of oil, then begin adding your water. Mix until dough begins to form a ball around the dough hook. If your dough is still tacky, add a little more flour, a 1/4 cup at a time. Next, grease a separate bowl with the remaining 2 tsp of olive oil. Place the ball of dough in the greased bowl and cover. Place in a draft free area for about 1 1/2 hours or until the dough has doubled in size.
For the Pizza Sauce: Place olive oil in saucepan over medium-low heat. Add onion and celery, cook for about 5 mins or until soft. Add garlic and cook for 1 minute. Reduce heat to low and add the remaining ingredients. Cook for 10 minutes, stirring occasionally.
Once your dough is ready, preheat your oven to 475 degrees. Turn dough over onto floured surface and cut into two equal pieces. Save one for later in an airtight freezer bag. You may store in the freezer for about 3 months. Place the dough you are using on a floured sheet of parchment paper. Stretch out the dough, tossing with your hands for the best results. You can use a rolling pin if that's easier for you, just make sure to lightly flour the rolling pin so the dough doesn't stick. Make a 12" circle with the dough. You want to roll the dough out slightly thin.
Place your pizza stone in the oven to get it nice and hot before you cook your pizza on it. Leave it in the oven for about 10 minutes. If you are using a pizza pan, skip this step.
Now, sauce your pizza, leaving about a 1/2 inch around the edges. Evenly sprinkle mozzarella cheese on top of the pizza.
Carefully remove the pizza stone from the oven. Gently slide your pizza onto the stone with the parchment paper. Bake for 5 minutes then turn down heat to 425 and bake for another 5 minutes. Remove pizza from the oven. Let cool, and serve!