1. Preheat the oven to 275°F.

2. Blanch the diced carrots for 2 minutes in salted water. Drain.

3. Cut the raw foie gras into approximately 2 cm thick slices. Season with salt and pepper. Set aside.

4. Mix the pollock fillets with a pinch of salt, pepper, egg whites, and cream. Incorporate the carrots and chives.

5. Line a 30 x 11 x 10 cm terrine with a sheet of buttered aluminum foil, leaving enough overhang on the sides.

6. Season the red mullet fillets with salt and pepper. Place skin side down on the bottom of the terrine. Fill with pollock mousse, smooth, and cover with foie gras. Season with salt and pepper generously. Press lightly.

7. Cover the terrine with parchment paper and fold the aluminum foil over it.

8. Cook for 45 minutes in the oven in a water bath.

9. Remove from the oven and let cool. Refrigerate for 12 hours.

10. Unmold the terrine and cut into thick slices; garnish with chives and langoustines sautéed in butter; serve immediately.