Scrub the lemon under hot water and blot dry. Using a vegetable peeler, remove the zest in thin strips. Arrange the strips on a baking sheet and place in the oven. Bake until dry, about 1 hour.
Place the lemon zest and peppercorns in a spice mill. Work in several batches if necessary. Gring the lemon and pepper to a coarse powder. Transfer to a jar, cover and store away from heat and light.