6 soft but dense burger buns or rolls
1. Remove the burgers from the refrigerator and set aside, away from direct sunlight in a cool place, to come to room temperature for about 15 minutes. Meanwhile, heat the grill.
2. Halve the burger buns and brush the bottoms with steak sauce.
3. Grill the burgers, brushing the tops with steak sauce after they are flipped. Just before the burgers are finished, add the buns to lightly toast. When the burgers are done, remove and rest under aluminum foil for about 10 minutes.
4. Add a large scoop of mushrooms to the bottom of each bun. Place a burger over the mushrooms and top with caramelized onions, then the bun top. Serve immediately.
To whet your appetite for the remaining finalists, here's a super-fast look at all the burgers we tasted.
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