Make the beurre blanc: Bring wine, vinegar, shallots, thyme, and bay leaf to a boil in a small saucepan over medium heat. Continue to boil until liquid has evaporated, 3 to 4 minutes. Stir in cream and boil until liquid has reduced by half, 4 to 5 minutes. Reduce the heat to low. Whisk in one piece butter until melted; repeat with remaining butter. Do not allow sauce to simmer, or it may separate.

Strain sauce through a fine sieve into a heat-proof bowl. Stir in chives, lemon juice, salt, and pepper. Set the bowl into a larger container full of hot water to keep warm until needed.

Start the halibut: Set an oven rack about 6 inches from the heat source and preheat the oven’s broiler. Pat halibut fillets dry; season with salt and pepper.

Heat oil and butter in a large skillet over medium-high heat until butter melts. Add halibut and cook until lightly browned on the outside and fish flakes easily with a fork, 2 to 3 minutes per side. Transfer to a baking sheet and let rest for 5 minutes.

While the halibut is resting, make the topping: Stir almonds, bread crumbs, and melted butter together in a small bowl.

Brush beaten egg over fillets, then cover with topping.

Broil fillets in the preheated oven until browned, 1 to 2 minutes, watching closely so they don’t burn.

Transfer fillets to individual plates, and spoon beurre blanc around them.