Rinse the trout with cold water, pat dry, salt and pepper inside and out, drizzle with lemon juice on the inside. Preheat oven to 200 degrees.
Wash the vegetables and cut them into pieces or sticks. Finely chop the herbs.
Briefly toss the vegetables in heated butter, season with salt, pepper and nutmeg. Fold in the chopped parsley or herbs.
Place the trout on a sufficiently large piece of aluminum foil (previously greased with butter) and fill with the vegetable mixture. Put any leftover vegetables around. Cut the lemon into wafer-thin slices and top the trout with it. Fold aluminum foil over it and cook the fish in a preheated oven at 200 degrees for about 20 minutes.