Topped with sautéed onions and melted blue cheese, these portobello burgers are delicious enough to satisfy even the most die-hard beef lover.
The balsamic vinegar glaze adds a subtle, sweet and savory quality that serves as a nice contrast to the tangy blue cheese.
Featured Ingredient: Balsamic Glaze
Our portobello burger recipe includes easy instructions for making the balsamic glaze (reduction) yourself and it only takes a few minutes, but you can also buy it bottled in just about any supermarket.
We think it’s a terrific condiment to have on hand because it gives a nice flavor boost to all sorts of foods.
In addition to glazing these portobello burgers, we drizzle balsamic glaze on vegetables like zucchini and bell peppers before roasting them, brush it onto grilled steak and chicken, and use it as an easy topping for meatloaf.
Balsamic-Glazed Portobello Burgers
- 6 portobello mushrooms
- 1/4 cup balsamic glaze (reduction), store-bough or see the instructions below
- 2 tablespoons vegetable oil
- 2 large sweet onions, thinly sliced
- Salt and freshly ground black pepper
- Pinch of sugar
- 6 ounces crumbled blue cheese
- 6 soft sandwich rolls
- Brush any dirt from the mushroom caps, remove the stems and reserve them for another use.
- Brush about half of the balsamic glaze onto the tops of the mushrooms, then set them aside while you sauté the onions.
- Separate the onions into rounds. Heat the oil in a large skillet over medium heat. Add the onions and season with salt and pepper.
- Sauté until the onions are soft, translucent and beginning to brown, 5 to 7 minutes.
- Preheat a gas or charcoal grill to a medium temperature (about 400°F).
- Oil the grates and add the mushrooms, gill side up.
- Grill for 3 minutes, then turn them over, brush with the rest of the balsamic reduction and grill until tender, about 3 minutes longer.
- Top each mushroom with a portion of blue cheese and cook just until the cheese begins to melt, 1 minute more.
- To serve, place a portion of onions on the bottom of each bun, add a cheese-topped portobello and serve immediately.
How To Make A Balsamic Reduction
- Place 1 cup of balsamic vinegar in a small, non-reactive saucepan and bring to a slow simmer over medium heat. Continue cooking, stirring occasionally, until it reaches a syrupy consistency and easily coats the spoon, 12 to 20 minutes.
- You can continue to reduce beyond this point but bear in mind that the vinegar will thicken even more as it cools.
- Remove from the heat, allow to cool completely, and transfer to a small jar. Cover and keep refrigerated until ready to use.