Large onions work best, I like the Spanish yellow or plain white onion. Core it from the root side and hollow it out to about three layers thick. Mix up a savory stuffing a good use of the onion guts,(I like sausage), with shredded hard cheese of your choice, loosely pack the hollow, put them into a cast iron skillet or roasting pan. Put about 2-3 inches of beef broth around the onions. Cover and shove them in a preheated 425* oven for 10 minutes then drop the temp to 350*, cook until translucent and soft to a tooth pick and 165*-175* in the stuffing.