Preheat the oven to 300 degrees F. Season the rabbit with salt and pepper. Place the rabbit in an oven-proof pan and cover with the duck fat. Add the garlic cloves and rosemary sprigs to the pan and season with salt and pepper. Cover the pan with aluminum foil and place in the oven. Slow cook the rabbit for about 2 to 2 1/2 hours or until the meat is very tender. Remove from the oven, cool completely in the fat and strain. Reserve 1 cup of the confit oil. Discard the rosemary. Meanwhile, in a saute pan, over medium heat, add 2 tablespoons of the confit oil. When hot, add the mushrooms. Season with salt and pepper. Saute until wilted, about 3 to 4 minutes. Carefully add the Marsala and cook until the liquid has almost evaporated. Remove from the heat and cool completely.

To make the rillette: Remove the meat from the rabbit, discarding the bones. In a food processor, fitted with a metal blade, combine the rabbit, 1/4 cup of the reserved confit oil, shallots, garlic, parsley, and Dijon mustard. Season with salt and black pepper. Process for 30 seconds, starting and stopping the machine several times. **Do not puree the mixture. Taste, and reseason if necessary. **If the rillette is not moist enough, add another 1/4 cup of the confit oil. Cover the rillette and store in the refrigerator. The rillette will keep for up to 2 weeks. Yield: about 3/4 of a pound Line a 12 1/2 by 4 1/2 by 3 1/2-inch terrine mold with plastic wrap, allowing the plastic wrap to hang over the sides of the mold. Dissolve the gelatin in the veal reduction. Line the terrine mold with a third of the rillette. Spoon half of the mushrooms over the rillette, pressing down firmly after each layer. Repeat the layering with the remaining rillette and mushrooms, finishing with the rillette on top. Slowly pour the gelatin mixture (about 1/2 cup at a time) over the terrine, letting the liquid soak into the terrine. Cover with plastic wrap and refrigerate for at least 4 hours or overnight. Carefully place the terrine mold in warm water to loosen the mold. Unwrap the plastic wrap and place on a serving platter. Slice the terrine into individual servings. To serve, spoon the sauce in the center of each plate. Toss the lettuce with the olive oil. Season with salt and pepper. Place in the center of sauce. Lay a piece of the terrine against the lettuce