Mix together the flour, water, oil and salt in a large bowl, using your hands, until a dough forms. Weigh out the dough and divide it into 1 1/2-ounce pieces. First, roll each piece into a ball, and then flatten into a disk. Dust a baking sheet with flour and lay out the disks, stacking parchment paper between if necessary. Keep covered with plastic wrap so they don't dry out. Heat oil to 350 degrees F in a large saucepot or Dutch oven. Fry the disks in batches using tongs to turn until golden brown and puffed, 2 to 3 minutes. Transfer to a cooling rack fitted into a baking sheet or a paper-towel-lined plate. Season with salt while still hot. Serve immediately.