Peel and finely chop the onion then gently soften in 2 tbsp oil. Chop the bacon and strip the thyme from its stalks. Zest the lemon and chop very finely. Stir bacon and thyme into the onion. Cook for about 10 minutes to crisp the bacon. Stir the zest into the onions and leave to cool.
Meanwhile, slit the sausage skins and remove the meat to a mixing bowl. Heat 1 tbsp oil in wok, add the spinach and toss with tongs for about 30 seconds until wilted. Tip into a colander to drain and cool. Squeeze until dry then chop.
Stir the cous cous into 150ml boiling water, cover, leave for 10 minutes. Coarsely chop the chestnuts. Add onions, spinach, cous cous and chestnuts to the sausage meat. Add the juice of the lemon, season generously with salt and pepper then mulch together until evenly mixed.
This recipe is intended for a Christmas meal to serve 10 to 12 people. Simply reduce the ingredients accordingly for smaller meals, or freeze the leftovers for future use. Frozen stuffing will need to be taken out to defrost 24 hours before serving and is ideal to make ahead of time so you aren't too rushed in the kitchen on Christmas morning.
Leftover stuffing can also be turned into burgers by shaping into patties, brushing with oil and roasted on a baking tray in a hot oven for 20 minutes.