I like the combination of sweet, nutty Gruyère and the slight sharpness of Parmigiano Reggiano in this galette. Sometimes instead of thyme, I use a slightly smaller amount of rosemary.
For a special dinner, you can make potato galettes in individual tart pans. The amount of ingredients in the recipewill fill (with a little to spare) four 4-1/2-inch tart pans with removable bottoms. Baking times will be just slightly shorter, but remember, you can bake these ahead, remove them from the tart rings, and reheat them on a baking sheet. A mini galette makes a lovely bed for a slice of beef tenderloin with a little sauce.