This gratin of fish with cheese, tomatoes and herbs is one of those recipes that looks fancier than it actually is. A handful of simple ingredients — cheese, cream, cherry tomatoes and fresh herbs — come together in the oven to make a dinner that feels special but is genuinely easy to pull off on a weeknight.
When you’re spreading the cheese and cream mixture over the fish, don’t panic if it looks like it won’t stretch to cover everything. It will spread out and melt beautifully once it hits the oven, so just dot it on as evenly as you can and let the heat do the rest.
This recipe is adapted from Rachel Allen’s Rachel’s Favourite Food at Home. The original calls for flat fish, such as plaice or lemon sole, but we like the meatier texture of a firm white fish like hake or cod instead. If you can’t get hold of both Gruyère and Emmental, just double up on whichever one you can find — or try a farmhouse cheese such as Glebe Brethan in place of the Gruyère if you can source it.
Serves 4
Ingredients
- 100 g grated Gruyère cheese
- 100 g grated Emmental cheese
- 1 tablespoon Dijon mustard
- 5 tablespoons cream
- salt and freshly ground black pepper
- 250 g cherry tomatoes
- 1 teaspoon chopped fresh thyme leaves or 2 tablespoons chopped fresh basil
- 750 g white fish fillets, such as hake or cod, skinned and deboned
- green salad, to serve
- boiled new potatoes, to serve
Method
Preheat the oven to 180°C.
Place the grated cheeses, mustard and cream into a bowl and mix well. Season with salt and freshly ground black pepper and set aside.
Cut the cherry tomatoes in half and place into a bowl. Season with a little salt and add the herbs. Mix well so the tomatoes are evenly coated and seasoned.
Lay the fish in a gratin dish (or individual ovenproof dishes) in a single layer if you can. Dot the cheese mixture over the fish, then scatter the tomatoes and herbs on top.
Transfer to the oven and cook for 20 to 30 minutes (or 15 minutes if using individual portions), until the cheese is golden brown and the fish is cooked through.
To serve, plate up a portion of fish with a big green salad and some boiled new potatoes on the side.
Frequently Asked Questions
Can I use a different fish for this gratin?
Yes. The original recipe uses a flat fish such as plaice or lemon sole, but a firm white fish like hake or cod works really well too and holds its shape nicely under the cheese topping. Choose whatever good-quality white fish is available to you.
What can I use instead of Gruyère or Emmental?
If you can only get one of the two cheeses, simply double the quantity of whichever one you have. A good farmhouse cheese, such as Glebe Brethan, also makes a lovely substitute for the Gruyère if you’d like to try something different.
Can I make this dish in individual portions?
Yes, this recipe works well in individual ovenproof dishes. If you do this, reduce the cooking time to around 15 minutes rather than the 20 to 30 minutes needed for one large gratin dish.
What should I serve with fish gratin?
A big green salad and boiled new potatoes are the classic pairing, keeping the meal light and fresh alongside the rich, cheesy fish.
You Might Also Like
- Buried Treasure Fish Pie
- Homemade Fish Fingers
Have you tried this recipe? We’d love to hear how it turned out in the comments below.
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