Heat the butter in a pan over a medium heat.
Add the onion, garlic and mushrooms and fry for 3-4 minutes, until the onion is soft, then season well with salt and freshly ground black pepper.
Place the mixture into a sieve to drain off any excess moisture. Press lightly to ensure as much liquid is removed as possible.
Place the mushroom and onion mixture into a bowl and add the breadcrumbs, lemon zest, mint and almonds. Mix well.
Stuff half of the mushroom mixture into the body cavity of each of the trout, then wrap the trout flesh around to seal the stuffing into the cavity.
Hold the trout flesh together by piercing with three or four cocktail sticks that have been soaked for five minutes in water.
Heat the oil in a large clean frying pan. Add the stuffed trout and fry for 5-6 minutes on each side, or until completely cooked through.
To serve, place the trout onto plates. If you like, serve with chips.