Fish and potato gratin

I love serving this comforting recipe for hosting on a winter evening. You could use another white fish like Tilapia or Halibut - but I think cod is the best option! I insist on adding parsnips to the mashed potatoes - a perfect pairing with the delicate fish flavour!

Servings: 6 

Preparation: 15 minutes

Cooking: 1 hour

Ingredients :

Puree:

• 4 russet potatoes, peeled and diced
• 2 small parsnips, peeled and diced
• 1 cup 2% milk
• ¼ cup unsalted butter
• ¼ tsp ground nutmeg
• 1 tsp kosher salt
• Pepper from the mill, to taste

Fish :

• 1 small yellow onion, finely chopped
• 225 g Portuguese or Spanish chorizo ​​(I use the Delisa brand), cut into small one-centimeter cubes
• 1 clove garlic, finely grated
• 250ml cream 35%
• ½ tsp cornstarch
• 1 tbsp dijon mustard
• 3 tbsp finely chopped flat-leaf parsley
• 2 tbsp finely chopped tarragon (optional)
• 2 large handfuls of baby spinach (about 71g)
• Zest of a lemon
• Juice of half a lemon
• 500g Icelandic cod fillet, cut into one-inch pieces

Trim :

• 1 cup panko breadcrumbs (or homemade breadcrumbs made with fresh bread)
• ½ cup grated parmesan cheese
• 1 tbsp olive oil

Steps:

1. Preheat the oven to 180°C/375°F.
2. Add potatoes and parsnips to a pot. Fill with cold water, salt the water and bring to a boil. Cook until vegetables are tender, about 20 minutes.
3. Meanwhile, heat the Le Creuset Oblong Dutch Oven (or a large skillet) over medium heat. Add a drizzle of olive oil and cook the onion and chorizo ​​until softened and starting to brown – about 5 to 6 minutes. Add the garlic and sauté for about a minute.
4. Add the cream and scrape the bottom of the pan with a wooden spoon. Bring to a boil, stir and add the mustard, parsley, tarragon, lemon juice and zest. Mix the cornstarch with a tablespoon of water. Add to the mixture, reduce the heat and add the spinach. Stir until it begins to reduce in the sauce. Add the fish pieces, stir, season with salt and pepper, turn off the heat and set aside. (If using a skillet, transfer the mixture to a ceramic baking dish.)
5. Drain the potatoes and parsnips. Add the milk and butter to the pot. Heat over a low heat until the butter has melted. Return the vegetables to the pot. Mash with a potato masher, season with salt and pepper. Carefully add the purée to the fish mixture. Spread to give a rustic effect.
6. Mix breadcrumbs, parmesan and olive oil in a bowl. Sprinkle over the gratin and bake for 25 to 30 minutes until the sides are bubbling and the top is golden brown.
7. Let stand for about 10 minutes before serving. Enjoy with a green salad! So good!