Delia’s roast beef is another option.
What I do is work out all the timings by writing it all out. This includes when to put the roast potatoes in, when to put the veg on and any Yorkshire puddings.
Beef is better as you can let the beef rest without worrying about it being underdone. Then you turn oven up and cook potatoes.
So basic outline:
Preheat oven. Prep meat, pop in oven. If you cook the meat on a bed of chopped carrot, onion, celery and some garlic you can use this veg in your gravy with the juices. Everything is strained so you don’t have lumpy gravy!
Prepare potatoes (peel, parboil), put a tray with fat (eg goose fat) in oven. When it’s time, pop potatoes in the oven. Remove meat when you need to and rest.
Prep veg. Start cooking about ten minutes before you want to serve up. Make gravy using meat juices and some veg water (I cheat and use bisto as well!)
Remove potatoes and pop in Yorkshire’s (I cheat and use pre made ones which only need warming - not frozen).
Serve up!