Combine the salt and 1/4 cup of the water in a large bowl.
In a small bowl, combine yeast and another 1/4 cup of the water. Stir to dissolve the yeast completely and set aside.
Add 1/2 cup of flour to the salted water and stir to incorporate.
Add the rest of the flour, stir, and then add the yeast mixture.
While stirring, add the rest of the water until the dough forms into a ball. If the dough is sticky, add additional flour, 1 tablespoon at a time, until the dough comes together in a solid ball. If the dough is too dry, add some more water, 1 tablespoon at a time.
Knead into a smooth, firm ball, cover with plastic wrap, and let rise for 24 hours in a very warm place (inside the oven works fine).
Preheat oven to 350º F.
Place a cooling rack in a large cookie sheet and brush with olive oil.
Arrange tomato slices on the rack, sprinkle with salt and pepper, and brush with olive oil.
Bake until tomatoes are tender, about 15 minutes.
Coat a 22x16-inch baking sheet with 1 tablespoon of olive oil. Transfer the dough to the sheet. Using your fingertips, press out the dough to fit the baking sheet. Let dough rest 10 minutes. Drizzle with 2 tablespoons of olive oil.