Thu Sep 21, 2017
After scoring a win with barbecue tofu—which just further went to prove that most anything can be made better with barbecue—I decided to take a chance on a repeat vegetarian success, but this time using portobello mushrooms. I've always been told, but have never quite been sold on the idea that portobellos are "meaty," which really just speaks to their heartiness more than flavor or texture in my opinion. That notion though led me to treat these mushrooms as "burgers," and one of my favorite burger topping combinations is grilled onions, cheddar, and barbecue sauce, so that was exactly how I served these up.
That success with barbecue tofu came from treating it in the same manner I would barbecue chicken, which started with the application of a rub, so I did the same thing here. Since meat is inherently moist on the surface, a rub easily clings to the outside, but for drier mushrooms, a little help was needed by an initial brushing of oil first.
Once oiled up, I gave each mushroom cap a generous dusting of my standard barbecue rub. My goal was to give these mushrooms the same strong barbecue flavor you'd find on chickens and ribs, so I saw no need to skimp in any way on the seasoning.
That was all there really was in term of prep for these, so it only took a couple minutes until I was off the grill where I started by cooking up an onion that I had cut into 1/2-inch high rings that I threaded onto a single skewer to make it stay together and be easily manageable. This made moving and flipping the onion around a snap while I waited for it to char and become crisp-tender, which took about seven minutes total over the fresh fire. Once done and set aside to cool a bit, I removed the skewer and roughly chopped the onion.
Next came the portobellos, which I cooked entirely over direct heat. When cooking mushrooms, my goal is get them to extrude a lot of their water content, at which time them become tender and delicious, but then pull them off before they cook much further and begin to dry out. For these mushrooms, that took about four minutes per side, and in the last minute or so of cooking, I brushed the caps with barbecue sauce which then caramelized during the short remaining time over the high heat.
Once done, I moved the portobellos over to indirect heat, flipped them all gill side up, and topped with onions and a slice of colby cheese. I then covered the grill and let them cook until the cheese was melted. Right before pulling the mushrooms off, I quickly toasted the burger buns because toasty buns are almost always better.
After placing one mushroom in each bun and finishing them up with a little extra barbecue sauce, it was time to serve. For me, the barbecue, onion, and cheese mixture is one that's hard to lose with, and it worked very well on these tender and full-flavored mushrooms. They had a great, complex barbecue profile that worked well against the hearty and earthy taste of the portobellos, which I wouldn't describe as meaty flavor-wise, but that description was apt in the sense that after finishing one of these, you were about as full as you would have been if it were a beef patty instead. So add another tick in the win column for a barbecue rub and sauce combo making a veggie option be all that it can be.
Barbecue Portobello Burgers
- Prep Time:
- 5 Minutes
- Cook Time:
- 20 Minutes
- Total Time:
- 25 Minutes
- 4 servings
- 1 large onion, cut into 1/2-inch slices and skewered horizontally so the rings lie flat on the grill
- 1/4 cup canola or vegetable oil
- 4 portobello mushrooms, stems removed and brushed clean
- 3 tablespoons barbecue rub
- 1 cup barbecue sauce
- 4 slices of colby cheese
- 4 hamburger buns
- Light one chimney full of charcoal. When all the charcoal is lit and covered with gray ash, pour out and arrange the coals on one side of the charcoal grate. Set cooking grate in place, cover grill and allow to preheat for 5 minutes. Clean and oil the grilling grate. Brush onion with oil, place on hot side of grill, and cook until softened and well charred on each side, about 5 minutes per side. Transfer onions to a cutting board, let cool slightly, remove from skewers, and cut into a medium dice.
- Brush portobellos all over with oil and season generously with barbecue rub on both sides. Place mushrooms on hot side of grill and cook until juicy and tender, 3 to 4 minutes per side. Brush mushrooms all over with barbecue sauce and cook until sauce has caramelized, 30 to 60 seconds more per side. Arrange mushrooms on cool side of grill, gill side up, and top each with onions and a slice of cheese. Cover grill and cook until cheese has melted, 1 to 2 minutes.
- Place buns, cut side down, on hot side of grill and cook until lightly toasted, 30 to 60 seconds. Transfer buns to a serving platter or plates, top each with a mushroom and additional barbecue sauce. Serve immediately.