Bourride with Lemon Aïoli

Ingredients

• 2 large carrots diced peeled
• 4 large egg yolks 
• 2 large fennel bulbs diced trimmed
• 5.5 cups fish stock 
• 4 pounds pacific halibut filets cut into 2-inch chunks
• 5 cups leeks white green chopped ( and pale parts only; 4 large)
• 8 servings lemon aioli 
• 0.3 cup juice of lemon fresh
• 0.3 cup olive oil extra-virgin
• 0.5 teaspoon saffron threads generous crushed ()
• 4  turkish bay leaf 
• 3 tablespoons x) 

Equipment

• bowl
• whisk
• pot
• wooden spoon
• slotted spoon

Directions

1. Transfer 1 1/3 cups aioli to medium bowl; reserve remaining aioli.
2. Mix lemon juice and saffron in small bowl; set aside.
3. Heat oil in large pot over medium heat.
4. Add leeks, fennel, and carrots; sauté 10 minutes. Stir in bay leaves and orange peel, then clam juice and lemon-saffron mixture. Bring to boil over medium-high heat.
5. Add fish; reduce heat to medium. Simmer until fish is opaque in center, occasionally spooning liquid over fish to submerge if necessary, about 8 minutes. Using slotted spoon, transfer fish to large bowl; cover.
6. Boil liquid in pot 10 minutes to reduce slightly.
7. Whisk 1/2 cup reduced liquid into bowl with 1 1/3 cups aioli, then whisk in egg yolks. Return yolk-aioli mixture to remaining liquid in pot. Using wooden spoon, stir constantly over medium-low heat until sauce thickens slightly, about 7 minutes (do not boil).
8. Remove from heat. Season with salt and pepper. Stir fish and any accumulated juices into hot sauce in pot; let stand until fish is heated through, about 5 minutes.
9. Divide bourride among 8 shallow bowls.
10. Garnish with chervil sprigs, if desired.
11. Serve remaining aioli alongside.