- Preheat oven to 200°C (400º F).
- Line a roasting or baking pan with parchment paper.
- Set aside 15 ml (1 tablespoon) of the duck fat.
- In a food processor, pulse the rest of the duck fat with the foie gras until smooth.
- Butterfly the chicken: Place the chicken on its back on a cutting board and using a chef's knife cut through the back along one side of the backbone. (If you prefer, you can cut out the backbone.)
- Turn the chicken over, open it and press to flatten.
- Lay the chicken flat, skin side up. Work your fingers under the skin of the breast and thighs, separating it from the meat. Take care to avoid tearing the skin. Spread the foie gras mixture under the skin. Refrigerate for 1 hour.
- Place the chicken in the pan, skin side up on middle rack in preheated oven. Rub the reserved duck fat over the skin. Sprinkle with breadcrumbs and season with salt and pepper.
- Insert a meat thermometer into the thigh without touching the bone.
- Roast until the thermometer reaches 77°C (170º F), 75 to 90 minutes.
Torchon-Style Foie Gras is available at upscale fine gourmet shops.