I have a question about step 3 on the recipe "No-Cream Gratin of Potatoes and Carmelized Onions" from Loulies. It says:
"Peel, and as thinly as possible (a mandoline works well), slice potatoes. Add to the caramelized onions in pan. Season with a pinch of salt and a few grinds of black pepper. Arrange onions and potatoes in medium-sized gratin dish. Cover with foil and bake until potatoes are tender about 35 minutes.