Put the chicken, pork and fatty bacon through a grinder.
Mix them together in a bowl.
Add the egg yolk, cream, cognac, Port and a little truffle juice.
Season with salt and pepper.

Remove any damaged or overly green leaves from the cabbage. Use only pale green unblemished leaves.
Remove them from the cabbages and cook in boiling salted water. Keep them slightly crisp and refresh in ice water.
Place the cabbage leaves one on top of the other; press them to extract any remaining water - this step is very important since it affects the weight and flavor.
Cut the leaves in half, removing the large central vein.
Set aside in a dry towel in the refrigerator so that it absorbs any moisture.

Cut the carrots, onion, celery and smoked bacon into 1 cm (3/8") dice.
Sauté in a saucepan with 20 g (4 tsp.) butter; do not let them color.
Add 50 ml (3 tbsp.) chicken stock and cook gently until the vegetables are soft. Set aside until serving time.

If the bacon is too salty or smoky, blanch it first: place it into boiling water and leave it until the water returns to the boil.

Since the bacon is already salty, season the dish only at the very end as needed.

Wrap the truffles with forcemeat stuffing (20 g / 2/3 oz per truffle); then wrap in cabbage leaves to form 110 g / 4 oz. balls.

Cooking tip
The weight of the ingredients is very important. For a truffle weighing approximately 10 g, you will need 30 g of stuffing and 80 g of cabbage. If the truffle is smaller, reduce the proportions of the other ingredients accordingly. When you wrap the truffle, begin with the lightest coloured leaves and end with the darkest ones to respect the cabbage's natural coloration.

When you wrap the truffle, begin with the lightest colored leaves and end with the darkest ones to respect the cabbage's natural coloration. 

Soak the caul fat overnight; squeeze it out and stretch it out. Wrap the truffle and cabbage.

Cooking tip
The caul fat plays an important role. Without it the cabbage will tend to soften in the oven and fall apart. The caul fat holds the "head" together and preserves its original shape.

Braise the cabbage-wrapped truffles for 35 minutes in equal parts chicken stock and veal stock in a 220° C (425° F) oven. Heat the vegetable garnish.

Presentation
On each plate, arrange some of the garnish and a wrapped truffle, cut in half. Spoon the sauce around and decorate with a few sprigs of chervil.