Roasted Mackerel with Radicchio, Black Olives, Red Peppers and Rosemary

I have three rules when cooking and eating fish: 1) eat sustainably; 2) only eat it if it’s fresh; and 3) do as little as possible to it. When I was younger and possibly more obsessive-compulsive than I am now, I strictly limited myself to five ingredients when cooking fish, not including salt. Yes, it was an unnecessarily lunatic culinary flourish, but it also taught me to respect the fish. The mark of a well-prepared fish dish is that two hours after you’ve eaten it, the flavor that you remember is the fish, not the accompaniments or the sauce.

Mackerel is certified as a sustainable fish on both sides of the Atlantic. It’s also remarkably affordable – in the UK, fresh mackerel usually costs about £6 – £7 a kilo. This is probably because mackerel is undervalued by consumers. People who claim they don’t like mackerel usually say “it’s too fishy” or “it’s too oily.” I adore mackerel, so I’m more than a little biased, but I’ll try to make a strong case for it. First, mackerel doesn’t have scales. This means it’s not kosher and not halal, but it also means that it’s a lot easier to prepare; mackerel skin is lovely, thin, and crisps up beautifully. Second, the natural oiliness of mackerel means it’s a lot more forgiving. You have to really abuse the fish to make mackerel dry. Sure, you aren’t necessarily going to want to deep-fry mackerel filets, but who’s deep-frying fish at home anyway? Third, the “fishy”, briny taste that people complain about is much less pronounced in fresh (as opposed to brined or cured) mackerel. The assertive taste also means that you can pair mackerel with strong, robust flavors. Mackerel does remarkably well with acidic sauces, and with herbs that you normally would associate with meat. Mackerel is also high in protein, minerals, calcium, and omega-3 fatty acids, which means that it makes your hair grow and your skin glow. Convinced yet?

This dish may be my new favorite way of eating mackerel. The mackerel is stuffed with black olives, red bell peppers (capsicum) and garlic, garnished with rosemary, and roasted atop a bed of fresh radicchio. The finished dish is aromatic, Mediterranean, and summery. It’s quick and simple to prepare, which means it’s a nice weekday dinner. I drizzled chilli-infused olive oil from the lovely people at Seggiano on my fish. This added a nice piquancy to the dish, but if you haven’t got it to hand, any other good olive oil will work as well. I love roasting whole fish (I think this may be the third whole roasted fish recipe I’ve blogged) but for those of you who don’t want to be fussed with fish bones and opaque white roasted fish eyes staring up at you, it’s easily adapted to filets; instead of stuffing the fish with olives, peppers, and garlic, make a little bed of these and lay the filets on top, and reduce the cooking time by half.


750 grams (about a pound and three quarters) whole mackerel or mackerel filets. If buying whole mackerel, ask your fishmonger to clean it for you.

1 large head of radicchio

50 grams (about two ounces) black olives, such as Kalamata, pitted and coarsely chopped

2-3 cloves garlic, sliced thinly

1-2 red bell peppers (capsicum), seeded and sliced thinly

4-5 sprigs fresh rosemary

Juice of 1/2 lemon

2-3 tablespoons chilli-infused olive oil, or a good quality extra virgin olive oil

Flake salt, such as Maldon’s

Fresh cracked black pepper


If you have a convection setting on your oven, preheat to 210 degrees Celsius (410 degrees Fahrenheit). Otherwise, preheat to 220 degrees Celsius (425 degrees Fahrenheit).

Wash the radicchio leaves and use them to fully line a shallow oven proof dish.

Lay the whole mackerel on the bed of radicchio leaves, and stuff the cavities, including the head, with the black olives, garlic, and red bell pepper slices. Drizzle the fish with the olive oil and lemon juice, sprinkle on the rosemary sprigs, and season the top of the fish liberally with salt and pepper (the underside of the fish gets plenty of flavor from the infused garlic and olives).

Roast, uncovered, for 18-20 minutes, or until the skin is crispy and the flesh feels firm to the touch. Don’t be distressed if your radicchio has browned in the oven; these crispy bits are delicious. Serve fish off the bone over the radicchio, with the olives and red peppers spooned on top.

Makes four servings.


18 thoughts on “Roasted Mackerel with Radicchio, Black Olives, Red Peppers and Rosemary

  1. I love mackerel, too! I’ve never understood why it’s not more popular; it’s an extremely tough sell here in the states. I like that you can use more assertive ingredients in its preparation and that it adapts well to so many different cooking techniques and it’s so good for you too! Great post!!

  2. I love mackerel and I’m especially partial eating it Japanese-style – seared in a smoking hot cast iron pan and serving it with shredded daikon, a few drops of soy sauce and a squeeze or two of lemon. I also like it served as sushi, where the mackerel is cured with salt and rice vinegar.

    I look forward to your posts, Susan, as I ALWAYS learn something new. I have branched out so much and stepped out of my zone because of you. Thanks for sharing this recipe!


    • Those flavor combinations sound amazing! Beautiful way to cut the oiliness of the fish. Makes me think of a bento box. I have never cooked with daikon but need to start experimenting with it.

      I am so honored by your comments; I think your food is gorgeous. Xx

  3. Eating fish has become so fraught, that we’ve mostly just quit doing it. Unfortunately, mackerel is seldom available here in our landlocked state (though you should see all the nearly extinct varieties they fly in to even the crummiest of grocery stores … always makes me want to cry). Anyhow, this looks like a wonderful way to cook mackerel and we might just try it in our French rental next month!

  4. Your rules are word for word exactly the same as mine… I adore mackerel by the way, it’s one of my favourite fish – it has such a depth of flavour. This recipe looks wonderful.

  5. You know who I blame? I blame the supermarkets. The mackerel they sell is too often on the turn, starting to rot, or just plain rancid. I guess part of the problem is that fresh Mackerel is absolutely divine, but it does start to degrade quickly. Ah well, at least this way it isn’t a target for over-fishing.

    Which is great because, as you say, it is one of the best fish to eat when fresh. Full stop. To my mind it’s better than Dover sole, turbot and most other premium fish. And you can have such fun with it when cooking. My current favourite is to bbq it with some rosemary and lemon (or bake it with lime and chilli over a bed of shredded leeks, spring onion and ginger. Yum.

    I love the recipe here, all those Mediterranean accents and the rather brilliant use of radicchio leaves. I guess their bitterness cuts the oil flesh beautifully. I want to go try it out now. I’ll just have to wait until the weekend and a trip to the fishmonger.

    • Interesting hypothesis. I enjoy blaming supermarkets for lots of things, and I think you’re right that they’re to blame for so many common (mis)perceptions regarding fish. I think I’d like to try curing/pickling mackerel next. Have you ever done it?

  6. This looks delicious…I LOVE mackerel. It’s probably one of my favorite fishes. And that “fishy” taste? I actually like that. I mean I’m aware that in other fish, a fishy taste/smell is usually not a good thing, but for example, Japanese pickled mackerel tends to have a little bit of that “fishy” taste and I just think it’s so delicious.

    Thanks for sharing! The pictures are beautiful!

  7. Pingback: Eating mackerel | Swineflustoppe

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