Roast onions

I think the last time I tried to roast an onion was at my mumu. It was a bit of a disaster. I forgot about roast onions, then, for a couple of years: last week I remembered them and made them for dinner. I did them in the same pan as some roast potatoes (small ones, about the same size as the onions.) Baking dish + alfoil lining + scrubbed potatoes + unpeeled little onions, in oven (approx 190C) for about 2 hours. I turned the oven down a bit more towards the end of the cooking time. They emerged very soft and caramelised on the bottom, where their onion juice had leaked out and become sticky-sweet. The potatoes also were infused with a sweet oniony taste, with crispy skins and fluffy insides. I didn't add any olive oil to the pan.
We ate the potatoes and onions with rare steak, steamed broccolini and a tomato and oregano salad. The next morning I found two little onions that didn't get eaten. I smooshed them on toast with some salt, pepper and butter: delicious.