Place trout in baking pan with water. Open trout and spread with 1/2 tsp butter. Place 2 slices of lemon inside trout, add 1 1/2 Tbsps lemon pepper. Close trout and spread remaining butter on top. Place lemon slices on top of butter and then sprinkle with remaining lemon pepper. Bake at 350 degrees for 10-15 minutes.
For microwave baking, place on microwave dish and do the same as above, except cook for 8 minutes on high setting.