In a bowl, combine the pureed black garlic and chopped toasted pine nuts. Mix well and set aside.

Pat the filet mignon steaks dry with paper towels. Season both sides generously with salt and freshly ground black pepper.

In a large skillet, heat the olive oil over medium-high heat. Once hot, add the filet mignon steaks and sear for about 4-5 minutes on each side for medium-rare, or until they reach your desired doneness. Remove the steaks from the skillet and let them rest for a few minutes.

Preheat your oven to 400°F (200°C). Once the steaks have rested, generously spread the black garlic and pine nut mixture on top of each steak, pressing lightly to adhere. Place the steaks on a baking sheet and transfer to the oven. Bake for about 5-7 minutes or until the crust is golden brown.

In the same skillet used for searing the steaks, add the cognac and cook over medium heat, scraping up any browned bits from the bottom of the pan. Allow the cognac to reduce by half, about 2-3 minutes.

Add the chicken broth and continue to cook until reduced by half again, about 3-4 minutes. Lower the heat and stir in the heavy cream and chopped chervil. Simmer gently for 2-3 minutes until slightly thickened. Remove from heat and whisk in the butter until melted and smooth.

Slice the filet mignon steaks in half if desired and place them on plates. Drizzle with the creamy cognac and chervil reduction. Garnish with additional chervil if desired.