Adapted from a recipe for Basque-style tuna in Slow Cooker Comfort Food by Judith Finlayson. Serves 6.
2 Tbsp olive oil
2 Tbsp piment d'Espelette (or hot smoked paprika), or more to taste
1 tsp kosher salt
1-1/2 lbs fresh tuna, cut into 1-1/2 inch chunks
1 large red onion, cut into large chunks
1-1/2 Tbsp chopped garlic (6 large cloves)
1 tsp fresh black pepper
1/2 cup dry white wine
2 cups chopped seeded tomato (don't need to peel)
2 cups diced Yukon Gold potato (2 large potatoes; don't need to peel)
1 cup chicken stock
2 bell peppers, cut into large chunks
1 Tbsp arrowroot
In a bowl, combine the olive oil, piment d'Espelette, salt and tuna. Stir well to coat all of the pieces of fish; cover the bowl, and refrigerate.
In a 4- or 5-quart slow cooker, add the onion, garlic, black pepper, wine, diced tomatoes, potatoes and chicken stock. Cook on HIGH for 2 hours, or on LOW for 4 hours.
Add the bell peppers, and cook on HIGH for 1 hour.
Then, add the tuna and all of the marinade to the slow cooker. Cook on HIGH for 30 minutes.
Use a slotted spoon to remove all of the fish and vegetables from the slow cooker; place in a large mixing bowl. Pour the liquid from the slow cooker into a small sauce pan, and set over high heat on the stove top.
In a small glass measuring cup, stir together the arrowroot with 3 tablespoons of water. Pour this slurry into the liquid in the sauce pan, and stir to ensure no lumps form. When the liquid has thickened slightly, pour it over the fish and vegetables.
Serve hot, over white rice, or let the dish cool completely, and refrigerate for up to 3 days.