I just chuck some sausages in a roasting tin/one of those big le creuset-esque earthenware dishes, with chopped sweet potato (don't peel), carrots, peppers, beetroot (the vacuum packed stuff with no vinegar) mushrooms, all chopped into biggish chunks, peeled and chopped red onion (small wedges) , with some garlic cloves crushed, salt and pepper, olive oil, smoked paprika, chilli flakes (can leave these out) and some cumin seeds, mix it all up so it's coated and bung it in the oven, 45 mins give it a mix/turn half way through. I then just put the dish on the table for people to help themselves with a bowl of green veg. DH likes crusty bread with it to mop up juices.
It takes 5/10 minutes to prep, oven does the work
ETA the same method works using new potatoes, parsnips, carrots, mushrooms, onion, garlic, sage and thyme, served with Yorkshires!