Everything tastes better as a slider, amiright? Especially when mushroom sliders are cooked with a magic mushroom spice blend, and then topped with a smoky, caramelized onion jam. Perfect for a crowd, or to enjoy alongside a bowl of soup!
It’s Super Bowl weekend, and it’s time to bring on da food! Oh, right, and the football, lol.
But, even diehard football fans know that game day is really all about the super snackage.
Now, I will happily admit that, in terms of party food selection, we vegetarians don’t have it too bad. I mean, give me a plate of sliced veggies, some cucumber dill dip, maybe some cheese cubes, and I’m good to go. Bonus points for Fritos and a margarita!
The one place where we’re often left standing with sad, empty plates, though, is in the sandwich area. I. love. sandwiches, but they’re usually piled high with deli meats or chicken salad.
So, let’s you and I take matters into our own hands, and create not just vegetarian sandwiches, but sandwiches that everyone will be hovering over, and sneaking seconds and thirds, completely forgetting about the fact that there’s not a shred of beef to be found.
And, I might be the lone weirdo of the world who thinks that sandwiches are even better as sliders, but I grew up in proximity to a White Castle, where sliders were novelties and completely awesome. They’re the perfect party food, because they’re portable, they’re stack-high-on-a-plateable, and they leave plenty of room for lots of salty snack indulgences (like Fritos and cucumber dill dip = my personal snack food weaknesses, although these days I usually go with a scrumptious dairy-free version made with cashew cream. Dreamy).
There are a couple of special things in this recipe to take note of. The first is the magic mushroom spice blend. Mushrooms are already delish, but it’s the Super Bowl, and I say that when you have the chance to kick flavors into high gear, you should take it! This simple spice blend, featuring dried porcini mushrooms, smoked paprika, and chili powder, tweaks out the earthy goodness of ordinary button mushrooms, and creates something special and craveworthy. Porcinis are the king of mushrooms, and they add a crazy amount of flavor, and in dried form, they’re convenient to keep on hand. (In this recipe, we’re grinding them up for the spice blend, so there’s no need to reconstitute them ahead of time.)
And of course, caramelized onions make everything amazing, and they’re just so flat-out easy to cook up: saute onions over low’ish heat for as long as you can take it. A half hour will do; 45 minutes is even better. Season them up with some balsamic butter, and a dose of the magic mushroom spice blend, and you’ve got some damn tasty sweet-and-spicy onions that you could eat right out of the pan with a fork. No kidding!
But save them for the mushroom sliders — you’ll be glad you did!
In addition to the finger-food portability of the slider, and the fact that the vegetarians and vegans in the crowd will love you for your thoughtfulness, mushroom sliders are awesome party food options because you can easily make enough for a crowd. This recipe will feed four people, but you can effortlessly double it.
The photos here show 12 mushroom sliders in a quarter-sheet pan; 24 should fit in a standard half-sheet, which means you could quadruple the recipe for a big party, as two half-sheets fit in standard ovens. (If you go the quad route, plan on cooking the mushrooms and onions in two batches, or in two separate pans each.)
You can also make and assemble the mushroom sliders an hour or so ahead of time, and then warm them up in the oven just before serving, so you can be present at your party and not stuck in the kitchen.
The mushroom sliders in these photos were made vegan (vegan substitutions are listed in the recipe), but if all your party peeps are okay with cheese, you can top these sliders with a tasty grated cheese, like Gruyere or Gouda, which gets all melty and wonderful in the oven.
Why everyone will love Mushroom Sliders:
- Sauteed mushrooms have a chewy texture and an earthy umaminess that provides a hearty substitute for meat, even beef lovers enjoy.
- Caramelized onions are practically a food group in themselves, lol. At the very least, they’re a super tasty condiment that tops these mushroom sliders perfectly.
- The magic mushroom spice blend and balsamic-maple syrup-mustard drizzle add extra special goodness that makes you want to go back for thirdsies.
Even after game day is long past, these sliders are awesome alongside a cozy bowl of soup. And as we move into warmer weather, they’ll also make a welcome option at cookouts, where vegetarians really get the short-shrift on sandwich fare. 😉
- 2 tablespoons extra virgin olive oil
- 1 large white onion sliced into quarter moons
- 16 ounces mushrooms thinly sliced (recommend cremini or button)
- palmful dried porcini mushrooms (4 or 5 pieces)
- 1 teaspoon smoked paprika
- 1 teaspoon chili powder
- 1/2 teaspoon garlic powder
- 1 tablespoon balsamic vinegar
- 1 tablespoon maple syrup or brown sugar
- 1 teaspoon Worcestershire sauce (or vegan Worcestershire sauce)
- 1 teaspoon Dijon mustard
- a few drops of liquid smoke
- 4 tablespoons butter or vegan butter melted
- kosher salt
- 12 slider buns
Preheat oven to 350°F. Line a rimmed baking sheet with parchment paper.
In a large skillet, heat one tablespoon of olive oil over medium until shimmering. Add the sliced onions, stir to coat, and lower heat to medium low. Slow cook the onions for at least 30 minutes, stirring occasionally. If they begin to brown too fast, reduce heat a little more, and add a little water.
Meanwhile, in a wide bottom saute pan, heat the remaining olive oil over medium until shimmering. Add the sliced mushrooms and stir to coat. Saute the mushrooms until tender, deep brown, and have released most of their liquids, about 15 minutes.
While the mushrooms cook, pulverize the porcini mushrooms into a powder using a mortar and pestle or, recommended, a spice grinder (if using a spice grinder, wait a few minutes before removing the lid, or a big puff of mushroom powder will stream out). Combine with the smoked paprika, chili powder, garlic powder, and a 1/2 teaspoon salt. Sprinkle 2 teaspoons over the mushrooms, and stir to coat.
Whisk together the vinegar, maple syrup, Worcestershire sauce, mustard, liquid smoke, and a pinch of salt. When the onions begin to turn golden, stir in 1 tablespoon of the balsamic mixture, a big pinch of salt, and continue cooking.
Also stir one tablespoon of the balsamic mixture, plus 1/4 teaspoon of the spice blend, into the melted butter, and pour the rest of the balsamic into the mushrooms.
Place the slider buns on the baking sheet and remove the tops. Brush the insides of the buns with the butter mixture. Spoon the mushrooms onto the bottoms, dividing them evenly among the 12 buns. Place a generous amount of the onions on top of the mushrooms, and then add the bun on top. (If there's leftover butter, lightly brush the bun tops with the extra.)
Bake for 15 minutes. Serve immediately.
Recipe doubles easy for a crowd. If using multiple sheet pans for the sliders, swap positions in the oven halfway through baking.
You'll have leftover porcini spice blend - use it in soups and chilis.
If you and your peeps consume cheese, top the onions with a generous amount of a grated cheese, such as Gruyere or Jarlsberg, before adding the bun on top. No need to extend baking time.