Preheat the oven 400 degrees F.
In an electric mixer, whisk the yeast, water, sugar and oil together to form a paste. Using a dough hook, add the flour and salt to the paste and mix until the dough comes away from the bowl and crawls up the sides of the hook. Remove the dough from the bowl and put into oiled bowl turning to coat the dough. Cover and let the dough rise until double in size, about 1 hour.
Turn the dough out onto a floured surface and divide into 4 (4-ounce) balls; cover. Let the dough rest for 10 to 15 minutes. Press each dough out into a 10-inch circle about 1/2 to 1-inch thick. Lightly brush the dough with olive oil.
Divide the potatoes into four portions and season with salt and pepper. Cover each dough with the potatoes, leaving a 1-inch border. In a small mixing bowl, toss the red onions and the duck confit with the extra-virgin olive oil or with a little truffle oil. Season with pepper. Place a layer of the red onions and confit on top of the potatoes. Sprinkle each pizza with the grated cheese. Drizzle each pizza with the truffle oil. Bake for 15 to 20 minutes or until the crust is crispy and golden brown. Garnish the pizza with chives.