Otak-Otak: Singapore's Grilled Fish Paste in Banana Leaf

Open the leaf, and the smell of fish and coconut rises

Spreading out a banana leaf in your kitchen starts a routine a little different from your usual fish dishes. You wipe the green leaf, soften it with steam, and lay a long strip of fish paste mixed with a red aromatic paste on it. When you set the wrapped leaf in the skillet, first you hear the sound of moisture steaming, then a little later the sweet smell of the leaf scorching. The steam that rises the moment you open it is unlike grilled fish or chawanmushi: it is the aroma of a Southeast Asian street stall.

Otak-otak (also written otah) is made by mixing fish paste with chiles, shallots, galangal, lemongrass, makrut lime leaves, coconut milk and so on, wrapping it in banana leaf and grilling it. It is eaten across Singapore, Malaysia and Indonesia, and the form changes by region: steamed or grilled, with more egg, with the fish left coarse. At Singapore stalls it is often written simply as otah in English, and it serves as a small side placed next to laksa or nasi lemak.

This article uses white fish that is easy to buy in an ordinary supermarket, makes the aromatic paste in a food processor, wraps it in banana leaf and cooks it in a skillet. What it keeps are the springiness of the fish paste, the roundness of coconut milk, and the aroma of steaming in a leaf wrapper. Fish can be approximated with sea bream or cod, sea bass or swordfish, but the aromas of galangal, lemongrass and makrut lime leaves are worth gathering at least once if you can.

Set beside another Singapore fish dish, the sour-hot stew assam pedas (in Japanese), you can see the difference between a dish stewed with tamarind and one grilled in a leaf. On days you want a lighter table, go to Hainanese chicken rice (in Japanese) or roti john (in Japanese). For a Malaysian street-stall connection, it goes well with the coconut noodle soup laksa (in Japanese).

What is otak-otak? A leaf-wrapped fish raised at the Straits street stalls

The interesting thing about otak-otak is that the fish is "grilled," yet the texture isn't that of grilled fish. The fish is minced and mixed with aromatics and wrapped in a leaf, so the surface doesn't dry directly while cooking. The leaf perfumes from the heat of a skillet or charcoal, and inside the fish, egg and coconut milk steam and set. The result is somewhere between fish balls, a terrine and chawanmushi, and it is moist when you cut it with chopsticks.

Otah eaten in Singapore and on the Malay Peninsula is a stall snack, a side next to plain rice, and a garnish for noodle dishes. Several small wraps are grilled and sometimes handed over on a paper plate just as they are. It is less a showy main dish than a way to add the umami of fish and hot aromatics to the table in small amounts. So when you make it in your own kitchen, too, it is closer to the local way not to make the fish thick, like a big hamburger.

There are big regional differences too. Around Muar in Malaysia, long leaf-wrapped red otak-otak is famous, and in Peranakan households coconut milk, egg and aromatics are sometimes combined to make it smoother. In Indonesia there are other lines of otak-otak in places such as Palembang and the Riau Islands, where it may be steamed and then grilled, or whitish fish paste is served with peanut sauce, so the look and taste both change. This article leans toward the red aromatics and leaf-grilling seen on Singapore tables.

The thing to avoid most when making it elsewhere is ending up with "ordinary fish patties." Binding with breadcrumbs or wheat flour makes it easier to handle but loses the tenderness of fish that sets inside the leaf. What matters is to set it with egg, the protein in the fish, a little potato starch and coconut milk, and not to overcook it.

Ingredients: wipe the fish dry and decide the aromatics first

Serves 4, making 8 long packets. Alongside rice allow 2 per person, or divide into slightly smaller packets, 10 in all, as a light snack. Prepare eight 30 cm square banana leaves and keep several small leaves aside for patching tears.

Shopping: look at the aromatics, not the fish

Fish, eggs, cucumber and rice are fine from a neighborhood supermarket. Where shopping gets hard is coconut milk, galangal, makrut lime leaves, banana leaf and the tools for making the aromatic paste. Galangal and makrut lime leaves in particular give the aroma of Southeast Asian leaf-wrapped dishes all at once.

Coconut milk is what connects the hot aromatics and the fish. Milk or fresh cream takes the aroma in another direction. Any left over can go into nasi uduk (in Japanese) or soto betawi (in Japanese).

Galangal has a hard, citrus-like aroma unlike ginger. You can make it with ginger alone, but if you want to approach the aroma of otak-otak, it is an ingredient worth adding even in a small amount.

Makrut lime leaves, cut into thin strips and mixed into the paste, keep their aroma after grilling. When lemongrass alone makes it too round, the green aroma of the leaves cuts the fat of the fish.

The aromatic paste can be made with a knife alone, but chopping lemongrass and galangal fine takes time. With a small food processor it's easy to stop at a coarse paste, and you can reuse it for ayam betutu or a sambal substitute. A tool you already own is enough, so no dedicated product is called for here.

Method: wrap in leaf and let the aroma come in from outside

For otak-otak, if the fish mixture is too thick the outside dries before the center sets. Aim for long and slim, 1.5–2 cm thick, and steam-grill it in the leaf. Too high a heat in the skillet scorches only the leaf, and too low makes it watery, so start at medium and lower to medium-low once it has color.

A decision table for getting closer to the real thing in a home kitchen

Otak-otak sounds hard from the ingredient names alone, but it becomes easier to make once you separate what you can substitute from what you'd like to keep. What to keep is wrapping in leaf, the red aromatics, coconut milk and managing the moisture of the fish. The kind of fish can be chosen to suit your fish counter.

For fish, cod gives a soft, light result. It has a lot of water, though, so sprinkle it with salt, leave it for 5 minutes and wipe off the liquid thoroughly so it holds together. Swordfish is easy to handle and gives springiness, but some individual fish with little fat turn a bit firm. Sea bream and sea bass have a refined aroma and go well with coconut milk.

On days you can't find banana leaf, you can wrap in parchment paper and then in aluminum foil and grill. But the green aroma of the leaf won't be there. Treat the first time as practice in wrapping, and look for frozen banana leaf next time to notice the difference. To broaden your feel for cooking with banana leaf, Venezuela's hallaca (in Japanese) and the Central African Republic's maboke (in Japanese) can be read side by side as dishes that use the leaf as a "vessel of aroma."

Failure causes: watery, tough, only the leaf scorches

Most wateriness is decided by how you prepare the fish. If you use frozen fish, thaw it slowly in the refrigerator and also discard the liquid that collects on the plate, not just the surface moisture. Washing the fish adds water and loosens the paste. If the smell bothers you, don't wash it: sprinkle with salt, leave for 5 minutes and wipe the moisture off with paper.

Toughness changes with the cooking and the fineness of the paste. If you aim for a smooth fish terrine and run all the fish for a long time, it becomes too uniform and dense when grilled. Pounding half coarsely and making the other half into paste is the least likely to fail in a home food processor.

Storage and reheating: the leaf's aroma is best on the day

Grilled otak-otak smells best on the day it is made. If there are leftovers, let them cool without opening the leaf, put them in an airtight container and finish within about 2 days in the refrigerator. To reheat, put the packets in a skillet and warm over low heat for 3 minutes per side. In a microwave, open the leaf, put it on a heatproof plate, cover loosely with plastic wrap and heat at 600 W for 40–50 seconds. The microwave tends to drive off the aroma, so the skillet is better if possible.

If freezing, the grilled packets are better than the uncooked mixture. The uncooked mixture tends to release water on thawing and loosen. Cool the grilled packets, wrap them one by one in plastic wrap, and count on about 2 weeks in the freezer. To reheat, thaw in the refrigerator for half a day and bring them back slowly in a skillet over low heat.

White rice is the basic accompaniment. Adding cucumber and lime lightens the richness of fish and coconut. To go street-stall style, you can put rice, cucumber and heat on one plate like nasi lemak (in Japanese). If you add a soup, a light chicken soup or stir-fried greens won't compete with the aroma of the otak-otak the way a sour sinigang would.

Frequently asked questions

Q1. Can I make it without banana leaf?

Yes. Wrap in parchment paper, then in aluminum foil, and heat in a skillet or toaster oven. But the green aroma of banana leaf and the toasty smell from grilling it will be weaker. It works as cooking practice, and from the second time on, look for frozen banana leaf and you'll notice the difference.

Q2. Which fish suits it best?

For the first time, swordfish, sea bream and sea bass are easy to handle. Cod also works, but it has a lot of water and breaks easily, so salt it and wipe off the moisture before using. Mackerel has a strong aroma and brings out the local feel, but in a home kitchen the fishy smell can win out. If you use it, choose very fresh fish and make the aromatics a little stronger.

Q3. I don't like coconut milk.

Reduce the amount from 120 ml to 80 ml and add 2 tbsp water. If you leave it out completely, the fish paste tightens and the heat feels angular. Replacing it with milk or fresh cream moves it away from the Southeast Asian aroma, so reducing the amount first is more natural.

Q4. Can I cook it in an oven or toaster oven?

Yes. Arrange the packets on a baking sheet and bake in a 200°C oven for 12–15 minutes. Turn once partway, and confirm 63°C or higher at the center. A toaster oven has heat close by and the leaf scorches easily, so lightly cover with aluminum foil at first and take it off for only the last 2 minutes to avoid failure.

Q5. Can I make a non-spicy version for kids?

You can, but with zero chile the aroma also weakens. Use 2 dried chiles with the seeds removed, and put the sambal for the final touch on a separate plate for the adults. To make up for the missing heat, give a little more punch with makrut lime leaves, lemongrass and lime so it doesn't taste vague.

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