Put milk, pepper and salt in a zipper bag. Give it a couple of shakes. Add the trout, seal bag and put in cool spot for 10 - 15 minutes.
Melt butter in iron skillet over campfire. Dip trout in the flour to coat well. Put trout in skillet and brown trout on both sides. Put lemon on the trout and coat both sides. Put several thin lemon slices in bottom of skillet, put trout on top. Move skillet to a milder heat and continue cooking for 8-10 minutes or until flaky.
*** serve with lemon slices and lemon wedges, baked potato and a salad..... a 5 star meal under a million stars!