1Combine the flour, salt and yeast in the bowl of a stand mixer. Add the water. Using the dough hook, knead on low speed for 5-6 minutes or until the dough is smooth and elastic.
2Cover the bowl with plastic wrap and let the dough proof in a warm place for 1 hour until doubled in size.
3Turn the dough onto a lightly floured countertop and divide evenly into four pieces. Shape each piece into a smooth ball.
4Lightly sprinkle two baking sheets with the semolina mix and place the dough balls 4-inch apart on the sheets. Drizzle a little oil over each ball and spread to coat dough. Cover the with plastic wrap and refrigerate for at least 6 hours or up to 5 days (refrigerating the dough for 1-3 days is ideal but it can be refrigerated for up to 5 days). NOTE: To make the semolina mix, combine equal quantities of semolina and plain flour. Store in an airtight container in the pantry.
5When ready to prepare pizzas, remove the dough from the refrigerator and stand, covered, at room temperature for 1 hour.
6Meanwhile, for the topping, use a mandolin to very thinly slice the potatoes. Combine the crème fraîche and garlic in a small bowl. Season with salt and pepper. NOTE: For even cooking the potatoes need to be very thinly sliced and translucent.
7About 20 minutes before the dough is finished resting, select the WOOD FIRED setting and preheat the oven (preheat can take up to 20 minutes).
8Sprinkle a clean countertop generously with the semolina mix.
9Transfer one dough ball to the prepared countertop. Keep the remaining dough covered to prevent it from drying out.
10Coat the dough ball in the semolina mix and working from the center, press it into a 6-inch round, leaving a ¾-inch border, then gently stretch it into a 9-inch-11-inch circle.
11Lightly sprinkle the pizza peel with the semolina mix. Carefully transfer the dough onto the pizza peel, gently shaking off any excess semolina mix.
12Spread one-quarter of the crème fraîche mixture over the dough, leaving a ½-inch-¾-inch border. Top with one-quarter of the potatoes in a single layer, slightly overlapping. Sprinkle with one-quarter of the fontina and rosemary. (Note: fontina cheese can be replaced with Gruyere, provolone and gouda, if preferred).
13Use the pizza peel to transfer the pizza to the oven. Cook for 2 minutes, until the crust is spotted brown and the potato is tender.
14Slide the pizza peel under the pizza, remove it from the oven and transfer to a cutting board. Lightly drizzle with oil and sprinkle with salt flakes. Cut into slices to serve. Repeat with the remaining dough and topping ingredients.