Portobello Mushroom Burger

Not all burger lovers are carnivores, so I have this great Portobello Mushroom Burger recipe up my sleeve. It’s great on the grill too!

Portobello Mushroom Burger 

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  • 4 large portobello mushrooms, stems removed, caps left whole
  • 2 tablespoon plus more for buns of very good olive oil
  • ½ cup water
  • 2 tablespoon red wine vinegar
  • salt and pepper
  • ⅔ cup grated mozzarella cheese
  • 24 whole basil leaves
  • 8 strips of roasted red bell pepper (from a jar is fine)
  • 2 very good tomatoes (2 center section ½ inch slices is all you will need, save the rest of the tomatoes for another use.
  • 30 kalamata olives, or to taste
  • 4 very good kaiser rolls cut in half


Pre-heat the oven to 400 degrees. Cover a large rimmed baking sheet, or appropriately sized ovenproof plate with foil. Toss mushrooms with oil, water red wine vinegar; season with salt and pepper. Arrange the mushrooms stem side down; cover loosely with more foil. Roast until tender, 30 to 45 minutes.

Meanwhile brush the cut side of all the Kaiser roll halves with a little olive oil. Then set them oiled side down onto a grill pan, until lightly toasted.

When the mushrooms are ready remove the top layer of foil and turn each cap over so that the ribs are facing up. Carefully drain off any of the accumulated liquid. Fill each cap with some of the grated cheese. Set the caps under a broiler until the cheese is bubbly and beginning to brown.

Lay the toasted rolls out on a large surface or serving tray. Cover the tops of each roll with 5–6 whole basil leaves. Top the basil with a mushroom cap. The push 5 or 6 kalamata olives into the melted-cheese. The cheese should act like glue keeping them from rolling off the “burger”.

On the other side of the roll layer the red bell pepper and tomato. Invert the top onto the bottom of the burger.

This is a messy burger so I advise cutting it in half to make it easier to handle.