Sauté the chicken and meatballs in plenty of butter.

Remove the chicken and meatballs once fully cooked.

Add the chopped mushrooms to the remaining butter and cook.

Remove the mushrooms when they are cooked through.

Add 3 tablespoons of flour to the remaining butter and stir to make a roux.

Add the chicken broth and whisk vigorously. Then add the heavy cream.

Return the chicken, meatballs, and mushrooms to the sauce.

Season with salt and pepper.

Let simmer for a few minutes.

Cut the "lid" off the puff pastry shell.

Spoon the vol-au-vent filling into the shell.

Serve hot with fries, potatoes, or rice.