I don't do Xmas, but I have been known to cook 5 course meals. Due to arthritis I can't cook from scratch the way I used to.
Buy pre prepped veg, wither use a steamer or microwave the bag the veg comes in. If you are using a steamer it can all be prepped the day before.
If you are cooking more than you usually would your oven needs more time, the heat dissipates, this is why on MKR and other cooking shows dishes that have worked perfectly for years suddenly don't work.
Jamie Oliver didn't invent those butters they have been around for decades, anyway they can be done ahead of time and frozen in ice cube trays.
Easy make ahead starters
Chicken liver pate - make in individual ramekins.
Melon and Parma ham.
soup - make ahead and freeze,defrost the day before and heat in a slow cooker.
pork and chicken terrine.
Terrine recipe
2-3 packets of streaky bacon
1 pack of chicken livers - these are usually sold frozen
2-3 packs of different sausages, cumberland,pork and lincolnshire are my go tos
1 packet of chicken goujons
1 metal loaf tin.
Line the tin with the bacon, start with the sides and have the bacon overlapping the sides so you can fold in after, once the sides are done cover the bottom with bacon.
Take a sausage, prick with a knife and take the skin off,l cut / pull in half and make into a ball. Do this with the other sausages
fill the lined tin with alternating sausage meats, chicken and chicken livers, press down as you go.
Once it is full fold the bacon over and bake in the oven for 30 mins.
When you take it out there will be a lot of grease, pour this off and add a weight while the terrine cools so more grease/fat comes out.
Serve in slices with bread and a couple of salad leaves.