Go meatless with these Grilled Teriyaki Portobello Burgers! Juicy teriyaki glazed portobello mushrooms are topped with grilled onion and pineapple, extra teriyaki sauce and sprouts! Wrap this burger in butter lettuce leaves or bun of your choice with a smear of the most amazing honey wasabi mayo!
In a small bowl, whisk together mayo, garlic, honey and desired amount of wasabi paste. Refrigerate until ready to serve.
*I use wasabi powder and mix it with a little water until it forms a paste. Then I add a pea-size amount at a time until I get the flavor I want. A little wasabi goes a long way, so only add a little at time and taste as you go.
MAKE THE PORTOBELLO BURGERS:
Preheat your grill to medium-high or about 400℉ (or 200℃).
Brush the underneath side of the portobellos with the teriyaki sauce, and spritz with the olive oil mister. Lightly mist both sides of the pineapple and onion slices with olive oil as well. This helps to keep them from sticking when grilling
Once your grill is hot, place the portobello burgers (teriyaki or underneath side facing down), and the pineapple and onion slices onto the hot grates. Generously brush more teriyaki sauce on the tops of the mushrooms. Close your grill lid and grill for 8 to 10 minutes or until good grill marks form.
Then carefully turn the portobello burgers, pineapple and onion slices. Close the grill and continue grilling for 3 to 4 minutes more.
Open the grill and top the the burgers with slices of gouda cheese. Close the lid if the cheese needs help melting, it should only take a few minutes. Remove the burgers, grilled pineapple and red onion.
SERVE:
Divide a few butter lettuce leaves onto four plates. Add a dollop of the honey wasabi mayo and top with a grilled teriyaki portobello burger, slices of grilled red onion, pineapple and more teriyaki sauce if desired. Garnish with sprouts and a sprinkle of sesame seeds.