Adapted from Great Food Without Fuss by Frances McCullough and Barbara Witt
I adapted this recipe from a really good cookbook. It's out of print, but you can usually still get it from Amazon or Jessica's Biscuit, often at a very discounted price, so you might want to check it out.
This is a rustic recipe originally from Julia Child. It's very easy and an unusual addition to your table. But it is an delicious addition not a star performer. When I make it, I clean the onions off with a damp cloth because I don't want to dislodge the papery skin, and I always use whatever sweet onions are available in the store.
Someone who made a comment apparently found the following instructions confusing, so I went back and checked the recipe I adapted this from to see if I left a step out. I didn't, so I guess I should add that the amount of time this takes will, of course, depend on the size of the onions. If they are done before the rest of the meal, the onions can be kept warm between the time they are soft enough to pierce with a cake tester and slitting the tops to butter and eat, and it won't make any difference in how they taste. The first time you make it, you might want to leave yourself a lot of time, like 45 minutes, and then you will be better able to gauge it for yourself the second time.
If you like onions, I think you will like this.
Big Baked Onions
1 large sweet onion per person
Preheat the oven to 400 degrees. Cover a baking sheet with a piece of foil, which you should crumple so the onions will stand up on it. Put the onions on the foil root side down.
Place the pan in the middle level of the oven, and bake until the onions are soft throughout when pricked deeply with a cake tester or skewer.
Slit the tops, and place a pat of butter in each. To eat, scoop the warm buttery flesh out of the surrounding skin like you do when eating a baked potato (except don't eat the onion skin).
To see just the recipe, click here.