I first started replacing some of the ground meat in my burger patties with finely chopped vegetables in an effort to eat more sustainably; it was a small thing I could do to eat a little less meat and a few more plants. But once I tasted my first blended burger, all that went out the window. The fact is, they just taste better.
While most blended burgers rely on about 25% veg (or less), my newest burger recipe bumps the ratio up to 50:50. These burgers are half crimini mushrooms, half ground chicken. I like crimini for the color they give the burgers and because they're easy to toss into a food processor and pulse into a fine grind that mimics ground meat. (For what it's worth, you can also chop them by hand.) White buttons or portobellos work too-as would more expensive mushrooms probably, though I haven't tested them-so feel free to buy whichever best fits your vibe.
The mushrooms increase the burger's umami factor, making them so savory one taster was convinced they were eating a beef burger instead of mushrooms and chicken. The mushrooms also help the burger retain a lot of moisture; it's really nice and juicy.
Mushrooms are actually so juicy, though, that you have to rein in the moisture: Once they're salted and finely chopped, you'll pile the mushrooms into a kitchen towel and wring them over a bowl to expel the excess liquid. But here's a tip: Don't toss that liquid (which is basically mushroom stock). It may not be great for burgers, but it's still full of flavor. Combine it with water to cook some grains for tomorrow's lunch or add it to your next soup broth.
To make the burger patties, combine the squeeze-dried mushrooms with ground chicken and form the mixture into eight ¼-inch-thick disks. Making the patties thin means they cook quickly and thoroughly on the grill-it also means you can stack them two patties high, layered with melting Muenster cheese.
I like to round out my mushroom-chicken burgers with shredded lettuce, grilled onion, sweet pickles, a swipe of mayo (Blue Plate, please), and a condiment that's hit my radar more recently: curry mustard. I love the mustard made by Brooklyn Delhi, but there are several brands available. Brooklyn Delhi's is a combination of coarsely ground mustard seeds with tamarind, garlic, and ginger, plus turmeric, paprika, and other spices. If you can't find it, you can approximate something similar by combining ¼ cup grainy mustard with a few teaspoons tamarind concentrate (or a similar sweet-tart sauce such as pomegranate molasses), a finely grated garlic clove, and a dash (maybe ½ teaspoon) of chaat masala or a comparable spice blend. But I really recommend buying a jar of the real stuff to taste it for yourself.
I like to sandwich these 'shroom-and-chicken burgers (any and every burger, really) between the squishy joy that is a potato bun. But listen, you can feel free to use brioche or ballpark-style or a mushroom bun (look at you, doubling down) or no bun at all if you'd like. And for that matter, feel free to load it with whatever toppings speak burger to you-even if that means leaving the patty plain. Because when the burger is this good, it almost needs nothing at all. Almost.