Preheat the oven to 230°C.
Squeeze the oranges, reserve the juice, stuff the ducks with skins, truss them, and season with salt and pepper.
Roast the ducks on a rack in a tray for 45 to 60 minutes.
Remove fat from the pan, pour orange liqueur over the ducks, and ignite to flame.
Deglaze the roasting pan with white wine and reduce to a thick sauce.
Add the orange juice, reduce by half, beat in the butter, and season.
Prepare the cabbage by removing outer leaves and veins before coarsely chopping.
Sauté the diced carrots in 25ml of oil until tender, then add garlic for a few minutes.
Fry the bacon in the same pan until crisp and combine with the carrots.
Cook the celeriac in the remaining bacon fat until tender and add to the carrot mixture.
Heat the remaining 25ml of vegetable oil and stir-fry the cabbage with salt.
Cover and cook the cabbage over high heat until it shrinks and becomes tender.
Mix all cooked vegetables and bacon together.
Serve carved duck garnished with orange segments, sauce, and cabbage.