The lightest, easiest way to cook (small) trout is to gut and gill the trout, then put the trout on a pointed green stick. Push the stick through the trout near the tail, again near mid-body, and then through the gill cover or mouth. Salt the trout ( I Like a mix of salt, garlic powder and cayenne pepper), then push the butt end of the stick into the ground next to a small fire. The fish should be done in 10-15 minutes, depending on size, heat of fire, etc. Eat the trout while it's still on the stick.
If the fish tends to slide down the stick while cooking, place a short second stick through the tail stick hole at right angles to the main stick.
This is the method used by Daniel G. of Tenkara USA, except he uses sea salt.