Slow Cooker Fish

Slow Cooker Tuscan Fish Stew

The fish is seared for a minute a side and then set aside. That minute is the only browning it gets, and it happens before the stew has even started cooking.

220 min · 4 servings · Slow cooker — LOW, fish added late

Seared white fish portions in a tomato broth with white cannellini beans and wilted spinach

About Darleen

on Recipesdarleen

Darleen is a mom who turned her slow cooker into a lifesaver, sharing cozy, easy-to-make recipes that bring comfort to busy days.

268 recipes by Darleen Vance

Published November 29, 2025

How Recipesdarleen publishes recipes

Cannellini beans and a 28-ounce can of diced tomatoes make a stew that could stand on its own. The fish is added to it rather than cooked in it, and only for the last twenty to twenty-five minutes.

There is no cream and no coconut milk here. The broth stays tomato-based and brothy.

Why This Recipe Works

  • Searing the portions for a minute a side gives colour and helps them hold together in the broth.
  • Two and a half hours softens the onion and garlic and lets the beans take on the tomato.
  • Cannellini beans are already cooked, so they only need to warm through and absorb.
  • Spinach in for five minutes at the end wilts into the broth while staying green.

Ingredient Notes

Cod or firm white fish
A pound and a half cut into four large portions — portions rather than chunks, and seared before they go in.
Cannellini beans
One 15-ounce can, drained and rinsed. They are a defining component of the stew, not a filler.
Baby spinach
Five ounces, in for the last five minutes only.

How to Make It

  1. Sear the fish

    Heat the olive oil in a skillet and sear the fish portions for about 1 minute per side; transfer to a plate.

  2. Build the stew

    Add the onion, garlic, tomatoes, broth, cannellini beans, Italian seasoning, salt and pepper to the slow cooker. Cover and cook on Low for about 2 1/2 hours.

  3. Fish in, to 145F

    Nestle the seared fish into the tomato-bean broth and cook 20 to 25 minutes, until the fish reaches 145 degrees Fahrenheit.

  4. Spinach and serve

    Fold in the spinach for the final 5 minutes until wilted. Serve immediately.

When the Fish Goes In

The stew and the fish are on completely different clocks. Three and a half hours total, of which the fish is present for less than half an hour.

  1. Before the cooker is switched on

    1 1/2 lb of cod in 4 large portions, seared 1 minute per side in olive oil

    Straight onto a plate afterwards. This is the only browning in the recipe.

  2. Hour 0 to 2 1/2, on LOW

    Diced onion, garlic, a 28 oz can of diced tomatoes, 2 cups of broth, a 15 oz can of drained cannellini beans, Italian seasoning, salt and pepper

    The stew builds on its own. Nothing delicate is in the pot yet.

  3. 20 to 25 minutes remaining

    The seared fish portions, nestled in rather than stirred

    Long enough to reach 145F and flake, short enough to stay in portions.

  4. 5 minutes remaining

    5 oz baby spinach

    Folded through to wilt into the broth while staying green.

  5. Immediately

    Nothing - it goes to the table

    Fish held in hot broth carries on cooking, so there is no resting stage.

Success Tips

  • Sear fast and hot. One minute a side is for colour, not for cooking it through.
  • Nestle the portions in rather than stirring them, so they stay in one piece.
  • Serve it as soon as the spinach wilts. Fish held in hot broth keeps cooking.

Serving Ideas

Four servings of seared fish portions in the tomato broth with the white beans and wilted spinach around them.

Frequently Asked Questions

Can I add cream or coconut milk?

No. The stew stays tomato-brothy with white beans and spinach.

How long is the fish actually in the cooker?

Twenty to twenty-five minutes, until it reaches 145 degrees Fahrenheit.

Is the searing step necessary?

It is how the portions get their colour and helps them hold together in the broth.

Recipesdarleen

Slow Cooker Tuscan Fish Stew

The fish is seared for a minute a side and then set aside. That minute is the only browning it gets, and it happens before the stew has even started cooking.

Prep
20 min
Cook
200 min
Total
220 min
Yield
4 servings

Slow cooker — LOW, fish added late

EquipmentSlow cooker · Skillet · Colander · Instant-read thermometer

Before you startThe fish is seared before the stew starts and goes back in only for the last 20 to 25 minutes, to 145F.

Ingredients

Instructions

  1. Heat the olive oil in a skillet and sear the fish portions for about 1 minute per side; transfer to a plate.
  2. Add the onion, garlic, tomatoes, broth, cannellini beans, Italian seasoning, salt, and pepper to the slow cooker. Cover and cook on LOW for about 2 1/2 hours.
  3. Nestle the seared fish into the tomato-bean broth and cook 20 to 25 minutes, until the fish reaches 145°F.
  4. Fold in the spinach for the final 5 minutes until wilted. Serve immediately.