Preparation Melt butter in a 7 1/2- to 8-inch nonstick skillet. Peel potato and cut crosswise into 1/8-inch-thick slices with slicer. Toss potato with melted butter, salt, and pepper in a bowl, then layer potato slices, overlapping slightly, in skillet. Cover skillet with a lid, or tightly with foil, and cook over moderately low heat until underside is golden brown, about 10 minutes. Slide galette onto a dinner plate. Invert skillet over galette, then, holding plate tightly against skillet, flip galette into skillet. Cook, covered, until potato is tender when pierced with a paring knife, 10 to 12 minutes more.
Preparation Melt butter in a 7 1/2- to 8-inch nonstick skillet. Peel potato and cut crosswise into 1/8-inch-thick slices with slicer. Toss potato with melted butter, salt, and pepper in a bowl, then layer potato slices, overlapping slightly, in skillet. Cover skillet with a lid, or tightly with foil, and cook over moderately low heat until underside is golden brown, about 10 minutes. Slide galette onto a dinner plate. Invert skillet over galette, then, holding plate tightly against skillet, flip galette into skillet. Cook, covered, until potato is tender when pierced with a paring knife, 10 to 12 minutes more.