Savory Portobello Mushroom Burgers

2 tablespoons olive oil

2 tablespoons balsamic vinegar

1 tablespoon Dijon mustard

2 cloves garlic, minced

½ teaspoon Worcestershire sauce

1 pinch salt and ground black pepper

4 large portobello mushrooms, stems removed

4 kaiser rolls, split

Preheat grill for medium-high heat and lightly oil the grate.

Whisk olive oil, balsamic vinegar, Dijon mustard, garlic, Worcestershire sauce, salt, and pepper in a bowl. Brush the mixture over the tops and bottoms of the mushrooms; let stand for 10 minutes.

Grill mushrooms on the preheated grill with the cover closed until mushrooms are browned and tender, about 10 minutes, turning once. Serve on kaiser rolls.