Squeeze the grapefruit, lemon and orange and split the vanilla pod.
Prepare the marinade by mixing the fruit juices, vanilla, salt and pepper.
Marinade the fresh cod fillets for 15 minutes then pour the remaining marinade into a container.
Lay the fillets in a microwaveable dish and cover with cling film.
Cook for 5 mins on full power.
While they are cooking, dilute the REGILAIT powdered whole milk with the marinade and bring to the boil, stirring constantly with a whisk until creamy.
Add a knob of butter.
Serve the fish with the sauce.

Chef’s tip:
Decorate with a vanilla pod.