Roll out pasta dough thinly using pasta machine and cut into fine noodles with the finest attachment. Wash the lemons, pull out very thin zests, squeeze the remaining lemon. Blanch the zests in boiling water for one minute, strain and drain well. Boil the pasta in plenty of salted water for about 15 seconds, strain and rinse briefly. In a frying pan, cream the butter, add the lemon zest, toss briefly. Add the pasta, capers, long pepper and a little water, heat and season with salt. Add cold butter, tossing constantly, so that the noodles become nice and “plump”. Serve in hot, deep plates.