Portabella mushrooms remind me of entries in a gardening contest for oversized vegetables. As it happens, that’s exactly what they are. Also spelled portobello (as in London’s Notting Hill market), these large brown mushrooms were named portabellas in an attempt to draw favorable attention to them.

They aren’t a separate species, but older crimini or brown mushrooms, sometimes labeled “baby bellas.” As they mature, the cap flattens out, often to four or five inches in diameter, covering prominent gills beneath. Because portabellas are harvested a week or so later than their smaller cousins, they have more concentrated flavor than those picked sooner and sold as criminis.

When buying portabellas, look for smooth tan caps and light-colored gills. Avoid those that have dried out and show curling or splitting around the edges. Any darkening or loosening in the gills is an undesirable sign of a specimen past its prime.

Like all mushroom varieties, they should be stored in the refrigerator in a container that provides ventilation, either a paper bag or open plastic bag.

To prepare portabellas, remove the woody stem, which is usually tough and not delicious (or add it to vegetable stock if you can’t bear to discard it). Using a damp cloth or paper towel, brush off any dirt from the top of the cap. Although the gills may be eaten, they’ll turn your dish an unpleasant murky brown color, unless you’re planning to cook them on the barbecue. Remove the gills by gently prying them away in tidy chunks with the tip of a spoon.

You can find portabellas featured in a wide variety of recipes, and they’re often seen on restaurant menus as a burger replacement, grilled and served on a bun.

For this preparation, lightly score the top of the cap to allow thorough heat penetration and prevent uneven shrinking as it cooks. If you choose to marinate, don’t soak them longer than 20 minutes, or the porous flesh will become sodden.

For the dish in the photo, sliced portabella mushrooms have replaced beef flank steak in spicy vegetable fajitas. In the recipe, I’ve listed spices for the sauce, but you can substitute a prepared fajita seasoning mixture like the excellent version available from Penzey’s.

The recipe for portabella pizza is easily adaptable to include your favorite toppings and cheeses. This version calls for the strong flavor of feta to stand up to the sturdy mushroom. Finally, the instructions for grilling portabella mushrooms are one way to create a vegetarian burger. These are not highly spiced, but you can readily expand on the basics with your favorite seasonings or steak sauce. Portabella mushrooms, another white meat.

Portabella Fajitas

1/2 lb portabella mushrooms
1 T balsamic vinegar
juice of 1 lime
3 T olive oil, divided
2 minced garlic cloves
1/2 t cumin
1/2 t paprika
1 t chili powder
pinch cayenne
1/4 t salt
1/4 t black pepper
1 yellow bell pepper
1 red or green bell pepper
1 large onion
4 tortilla shells, warmed
sour cream for garnish

Remove the stems from the mushrooms (discard or reserve for making stock). Gently brush away any dirt from the cap and remove the gills with the tip of a spoon. Cut the mushroom caps in 1/3-inch-thick slices; set aside. Whisk together vinegar, lime juice, 2 T olive oil, garlic and spices in a medium bowl. Add sliced mushrooms and stir to coat; marinate for 15 minutes.

Core and seed the peppers; cut lengthwise into 1/2-inch slices. Peel the onion and cut into slices.

Heat the remaining 1 T olive oil in a large skillet over medium. Add onions and peppers, cook until softened, about 5 minutes, stirring often. Add the mushrooms along with the marinade, cover and cook until tender, about 4 minutes. To serve, fill each tortilla shell with vegetable mixture and garnish with sour cream.

Portabella Pizza

6 portabella mushrooms
1 t olive oil
1/2 C tomato sauce
1/3 C sliced Kalamata olives
1/3 C sliced roasted red peppers
1/4 C sliced green onion
2 minced garlic cloves

Preheat the oven to 375 F. Line a baking sheet with parchment paper; set aside. Remove the stems from the mushrooms (discard or reserve for making stock).

Gently brush away any dirt from the cap and remove the gills with the tip of a spoon. Place the mushroom, cap side up, on the prepared sheet. Brush with olive oil and bake for 5 minutes. Remove from the oven and invert the mushrooms. Spoon tomato sauce into the center of each mushroom cap to evenly coat the flesh. Sprinkle with sliced olives, peppers, onion, garlic and feta cheese. Bake until cheese is starting to turn golden, about 15 minutes.

Portabella Mushroom “Burgers”

2 T olive oil
4 portabella mushrooms
salt & pepper

Preheat grill to medium high. Remove the stems from the mushrooms; do not remove the gills. Clean away any dirt from the tops with a damp paper towel. Brush both sides of the mushroom with olive oil, repeating after first coating is absorbed. Season both sides with salt and pepper. Place the mushrooms on the grill, cap side down, and cook for about 5 minutes. Turn and cook until tender, about 5 to 7 minutes. Serve on a hamburger bun with traditional garnish.