Vietnamese Caramelized Fish in Clay Pot (Ca Kho To)

Other Fast With Fish Published April 11, 2026

Ca kho to is Vietnamese home cooking at its most elemental — fish steaks braised in a dark caramel sauce with fish sauce, black pepper, and shallots until the sauce reduces to a thick, mahogany glaze that coats every surface. It is salty, sweet, savory, and slightly bitter from the caramel all at once. In Vietnam, this is the dish that rice was invented for — you eat it with a mountain of plain steamed rice, and the sauce soaks into the grains and makes every bite extraordinary.

The caramel is not dessert caramel. It is cooked until it turns nearly black and develops a deep, complex bitterness that balances the sweetness of the sugar and the salt of the fish sauce. This technique is unique to Vietnamese cooking and is the soul of this dish.

FASTING LEVEL: Fast With Fish
SERVINGS: 4
TIME: 40 minutes

INGREDIENTS

- 600g firm fish steaks (catfish is traditional; salmon, mackerel, or cod work well), cut into thick portions
- 3 tablespoons sugar (for the caramel)
- 1 tablespoon water (for the caramel)
- 3 tablespoons fish sauce
- 2 shallots, sliced into thin rings
- 4 cloves garlic, minced
- 1 tablespoon fresh ginger, sliced into thin coins
- 1 teaspoon freshly cracked black pepper (generous — pepper is essential here)
- 1 fresh red chili, sliced (optional)
- 1/2 cup coconut water or plain water
- 1 tablespoon vegetable oil
- 2 green onions, sliced into lengths, for garnish
- Steamed jasmine rice, for serving

METHOD

1. Make the caramel. Place the sugar and 1 tablespoon water in a small heavy saucepan over medium heat. Swirl the pan gently — do not stir — as the sugar dissolves and begins to bubble. Cook for 4-6 minutes until the caramel turns a deep amber, almost mahogany color. It should smell nutty and slightly bitter, not burnt. Immediately remove from heat — caramel goes from perfect to ruined in seconds.

2. Very carefully add 2 tablespoons of the fish sauce to the hot caramel. It will sputter violently — stand back. Stir until combined. The mixture may seize; it will dissolve again when heated.

3. In a clay pot, Dutch oven, or heavy-bottomed pan, heat the oil over medium heat. Add the shallots and cook for 2-3 minutes until soft and golden. Add the garlic and ginger, stir for 30 seconds.

4. Place the fish steaks in a single layer in the pot. Pour the caramel-fish sauce mixture over the fish. Add the remaining 1 tablespoon fish sauce, the coconut water, black pepper, and chili if using.

5. Bring to a gentle simmer. Cover and cook on low heat for 20-25 minutes, carefully turning the fish once halfway through. The sauce should reduce slowly, thickening and darkening as it concentrates. By the end, there should be only a few tablespoons of thick, glossy sauce clinging to the fish.

6. If the sauce is still thin, remove the fish carefully and boil the sauce for 2-3 minutes to reduce, then pour it back over the fish.

7. Garnish with green onions and serve immediately, directly from the clay pot, with a large bowl of steamed jasmine rice.

NOTES

- The caramel is the hardest part. Watch it constantly. Dark amber is correct; black is burnt and bitter beyond recovery. If you burn it, start over — there is no fixing burnt caramel.
- Catfish (ca basa) is the traditional choice because its firm, fatty flesh holds together during braising and absorbs the sauce beautifully. Salmon and mackerel are excellent substitutes. Delicate white fish (sole, flounder) will fall apart.
- Fish sauce is not optional — it provides the salt and umami foundation. Use a good Vietnamese brand (Three Crabs or Red Boat).
- Coconut water adds a subtle sweetness. Plain water works fine if unavailable.
- Ca kho to is even better the next day, reheated gently. The sauce continues to penetrate the fish as it sits.