Heat your pan to medium heat
Melt the butter with oil and add the trout fillets skin side down first.
After about two minutes carefully turn and cook for another 1-2 minutes.
Add the spring onions, parsley and lemon juice and leave it to cook through for another couple of minutes, until the trout is lightly brown.
To check that your fish is done, test it with a fork. If the trout flesh flakes off easily, the fish is cooked properly.
Serve straight from the pan with mashed potatoes mixed with spinach (or baby potatoes and asparagus)