Grate the cheese, strip the leaves from the thyme sprigs and grind some pepper over the cheese and thyme.
Line an oven rack with a sheet of baking paper. Place a few rounds of cheese on the baking paper and place the rack in the oven.
When after about 5 minutes the cheese has melted and is slightly browned (not too much), remove the rack from the oven. If you want you can place them (with baking paper) over a bottle so that they cool in a chips shape.