The Major Mistake That's Making Your Portobello Burgers Soggy
Before Impossible and Beyond burgers, before Boca and Dr. Praeger's, the perfect meatless burger patty already existed: the portobello mushroom. They're low in fat and calories, free of additives and artificial ingredients, and rich in vitamin B6 and other necessary nutrients. And of course, they're delicious and packed with savory umami flavor. They also couldn't be easier to prepare: Cut off the stems, clean and oil them, and throw them on the grill.
If you're looking to really impart some flavor into your portobello burgers, however, lots of recipes will advise you to start by marinating your mushroom caps before grilling. And while this technique can be a wonderful way to elevate your mushroom burgers, it can also lead to a massive pitfall: burgers that end up soggy, wet, and textureless.
The key to keeping your mushrooms from getting mushy, along with other mushroom mistakes you may be making, is care and moderation. Specifically, limit the amount of time you spend marinating your mushroom caps. While some ingredients, like beef, can marinate for hours on end, anything more than a quick dip can leave you with mushrooms that are hopelessly waterlogged.
Mushroom marinating for perfect results
There are countless portobello burger recipes on the internet, all of which suggest different blends of oil, vinegar, spices, and other flavorful ingredients in which to marinate your shrooms before grilling. But no matter how tasty the flavors may be, a soggy burger really kills the party.
You could be forgiven for over-soaking your mushrooms — many of the recipes you'll find online recommend marinating portobello caps for 30 minutes or more. But many experts say this is a risky move: You're better off marinating your portobellos for just 10 to 20 minutes. Unlike red meat, mushrooms are very absorbent thanks to their porous surface. Letting them sit in a marinade of your choice for 20 minutes max is the best way to ensure they end up tender, but still toothsome.
And of course, set yourself up for success by choosing the freshest mushrooms you can find and washing them properly. Try to buy them loose rather than pre-packaged so you can better evaluate their quality — look for ones that are intact, moist but not soggy or slimy, and free from any dry or wrinkly spots. And contrary to what you may have heard, washing your mushrooms won't make them soggy. Just toss the caps in a colander and quickly rinse away any debris, then lay them out on clean dish towels to dry completely.
Experiment with other elements to impart flavor
Once your mushrooms are marinated, simply toss them on an oiled grill or grill pan and cook for 3 to 5 minutes on each side. They'll release their excess moisture, and you'll score those lovely grill marks. A quick soak is all portobello caps need to tenderize their flesh and enhance their natural earthy, umami flavor. But if you're worried that a brief marinade won't impart as much flavor into your mushroom burger as you'd like, try jazzing up other parts of your burger to give it the kick you crave.
Use your favorite chip or veggie dip as an unexpected burger spread, swap your standard pickle chips for banana peppers or jalapeños, or top with fried onions or potato chips for a little added crunch. You could also make like Guy Fieri and bless your burger buns with a simple garlic spread.
The beauty of both burgers and mushrooms is their versatility. Love mushrooms, but still devoted to a classic beef patty? Consider swapping the buns for portobello caps for a tasty lower-carb and gluten-free alternative. Or, add mushrooms to ground beef when making the patties for a mouthwatering umami bomb. Just be sure, if you're using portobellos in any form, not to soak them to the point of sogginess.