Bouillabaisse with Garlic Aioli Toasts

To make the fish stock, in an 8-quart (8-l) stockpot over medium-high heat, warm the olive oil. Add the onion, carrot, fennel bulb and celery and cook, stirring occasionally, until softened and starting to brown, about 10 minutes. Season with a big pinch of salt.

Reduce the heat to medium-low and add the wine, stirring to scrape up the browned bits. Add the stock, fish bones, heads and bodies, star anise pods, bay leaves, peppercorns and thyme sprigs. Add enough water to cover the ingredients, about 2 cups (16 fl. oz./500 ml). Increase the heat to medium-high and bring to a vigorous simmer for 1 minute. Reduce the heat, cover and simmer gently, stirring occasionally, for about 2 hours.

Strain the stock through a fine-mesh sieve into a large bowl and skim off the fat, if desired. Taste and adjust the seasoning with salt; the stock should be briny and pleasantly salty. The recipe makes about 6 cups (48 fl. oz./1.5 l) stock; you will need 5 cups (40 fl. oz./1.25 l) for the bouillabaisse.

To make the bouillabaisse, in a large Dutch oven over medium-high heat, warm the olive oil. Add the onion and fennel bulb and cook, stirring occasionally, until softened and starting to brown, about 8 minutes. Add the garlic and saffron and cook, stirring occasionally, until fragrant, about 1 minute. Season with salt.

Reduce the heat to medium-low and stir in the stock and tomatoes with their juices. Increase the heat to medium and bring to a simmer, then simmer vigorously for 10 minutes. Add the halibut and cook until almost opaque, about 2 minutes. Add the mussels, clams and shrimp. Cover and cook until the mussels and clams open and the shrimp are opaque, 3 to 5 minutes. Add the scallops and simmer until opaque, 1 to 2 minutes. Discard any unopened mussels and clams. Remove from the heat and season to taste with salt and pepper.

Meanwhile, make the garlic aioli toasts: Position a rack in the upper third of an oven and preheat to 425°F (220°C). Alternatively, toast the bread on a stovetop griddle.

In a food processor, pulse the garlic several times until minced, then add 1 tsp. salt and pulse to combine. Add the whole egg and egg yolk and pulse to combine. With the machine running, slowly drizzle in the canola oil in a steady stream. Continue to blend until thoroughly combined. Add a squeeze of lemon juice and adjust the seasoning with salt. For a thinner consistency, add 1 to 2 tsp. water.

Drizzle the tops of the baguette slices generously with olive oil and place on a baking sheet. Transfer to the oven and bake until lightly toasted and golden, 6 to 8 minutes. If using a stovetop griddle, preheat the griddle over medium-high heat, then toast the baguette slices until golden. Spread the aioli over the toasts.

Ladle the bouillabaisse into bowls and garnish with the reserved fennel fronds. Serve with the garlic aioli toasts and lemon wedges. Serves 4 to 6.

Williams Sonoma Test Kitchen