Bourride: A French Fish Soup

1. Prepare the Fish Stock

Begin by creating a flavorful base for your soup. In a heavy pot, combine the fish bones, sliced leek, onion, fennel, and 4 peeled and smashed garlic cloves. Add the white wine, a few black peppercorns, a bay leaf, and thyme sprigs. Sprinkle a big pinch of salt over the top and pour in 4 cups of water. Bring this aromatic mixture to a boil, then lower the heat and let it simmer gently for 45 minutes. This will allow the flavors to meld beautifully, resulting in a rich and savory stock. Once done, strain the stock, discarding the solids, and set the liquid aside.

2. Make the Garlic Mayonnaise

While your stock is simmering, prepare the garlic mayonnaise. In a bowl, whisk together the egg yolks and a teaspoon of water until they're well combined. Slowly drizzle in the olive oil while continuously whisking, allowing the mixture to emulsify and thicken to a creamy mayonnaise consistency. Once thickened, stir in 4 garlic cloves that have been pounded into a paste with a pinch of salt. This mayonnaise will lend a velvety texture to your soup, adding depth and richness.

3. Prepare the Croutons

Preheat your oven to 375°F. Brush the slices of country-style bread with olive oil and place them on a baking sheet. Toast in the oven until golden brown. Once toasted, rub the warm croutons with a garlic clove to infuse them with a subtle, aromatic flavor. Set these aside for serving.

4. Season and Cook the Fish

Season the pieces of white-fleshed fish with salt. In a pot, bring the strained fish stock to a gentle simmer and add the fish pieces. Let them simmer until just cooked through and tender, then carefully remove them from the stock.

5. Combine and Finish the Soup

With the fish set aside, whisk the garlic mayonnaise into the hot stock, stirring gently until the broth thickens slightly. Be careful not to let it boil, as this can cause the mayonnaise to separate. Once thickened, return the cooked fish to the pot, allowing it to gently reheat in the creamy broth. Serve the soup hot, accompanied by the freshly made croutons.