A true Oklahoma original, onion burgers don’t even have an entry on wikipedia. When we say onion burger, we don’t mean burgers with grilled onions. We mean a patty pressed into a stack of onion and fried at high heat so that burger and onion become one. Until they make the giant one in El Reno next May, here are some giants in this local industry: Bunny’s Prepare to be transported to a simpler time, when bur...