Pull out the fat from the duck cavities and render over low heat. Rinse the ducks inside and out with hot tap water. Sauté the onions and celery in 2 to 3 Tbsp of the duck fat for about 5 minutes, then add the diced potatoes, the thyme and a little salt and freshly ground pepper to taste.
Turn the potatoes occasionally and when they are lightly brown, spoon the stuffing mixture into the 2 duck cavities. Place the ducks on a rack in a shallow roasting pan and put in preheated 375° F oven for 1 1/2 hours, then draw off all the fat. Mix the lemon juice with the honey and baste the ducks several times as you roast them an additional 15 to 20 minutes.
They should be golden brown and the drumsticks will turn easily in their sockets when ducks are done.
Servings: 4