Grilled Portobello with Basil Mayonnaise Sandwich

1 . Stage

Preheat an outdoor grill for medium heat and lightly oil the grate.

2 . Stage

Whisk vinegar, oil, and garlic together in a small bowl.

3 . Stage

Arrange mushrooms on a baking sheet with the gills facing up; brush with about 2/3 of the marinade and let sit for 3 to 5 minutes.

4 . Stage

Transfer mushrooms to the preheated grill with the gills facing down; grill, basting occasionally with remaining marinade, until tender, about 4 minutes per side.

5 . Stage

While the mushrooms are cooking, mix mayonnaise, basil, Dijon, and lemon juice together in a small bowl. Butter toasted rolls, then spread with mayonnaise mixture.

6 . Stage

Remove mushrooms from the grill and place on bottom buns. Top with lettuce, tomatoes, and top buns.