Best Veggie Sliders Recipe 

These vegetarian sliders are filling, satisfying, meatless, and definitely healthier than a greasy burger or typical cookout fare. Try them for a meatless weeknight dinner if you’re trying to lighten things up. For the filling, I caramelized a Vidalia onion in olive oil along with baby portobello mushrooms and pickles. The resulting combo is a meaty (minus the meat) sandwich that’s hearty, chewy, with subtle crunch from the onions and pickles. I used Bread and Butter Chips from Farmer’s Garden® by Vlasic®. I love pickles, but many brands are loaded with a ridiculous amount of sodium, which is why I’ve started pickling my own vegetables.  Thankfully the Vlasic pickles aren’t salt bombs and I love their sweet-and-tangy zip. They’re artisanal-quality, premium pickles, made with honest ingredients and no artificial flavors. They’re made with deliciously ripe cucumbers, whole garlic cloves, slices of red bell pepper, rounds of carrots, fresh herbs and spices, and hand-packed in glass jars.

Before filling the sliders, I coated the bread with fry sauce. If you’ve never had it, you’ve got to try it. Sometimes fry sauce is called Utah sauce or Utah fry sauce, but I waitressed in a dive bar in Minnesota in college and this is the sauce we served with wings and waffle fries so it’s not just a Utah thing. It’s two parts ketchup to 1 part mayo (use vegan mayo) with a splash of pickle juice. Now you have a use for pickle juice rather than just tossing it. The sauce is excellent on fries, but it makes a great sandwich spread and even for mayo-haters, it’s not overly mayo-ey.  I like a little food with my bowl of sauce or dip and can devour a batch on about 7 fries. I loved this filling mixture and didn’t even need buns. My family didn’t even realize it was meatless. Comfort food at its finest.

Ingredients for Vegetarian Sliders

To make these onion and mushroom sliders, you’ll need: 

Sweet Vidalia onion Olive oil Baby portobello mushrooms  Bread and butter pickles Pickle juice Slider buns or Hawaiian rolls Ketchup  Mayonnaise or Miracle Whip Onion powder

How to Make Vegetarian Sliders

These easy vegetarian sliders come together quickly and require minimal assembly. Here’s how the filling is prepared and the sliders are assembled: 

Can This Recipe Be Made in Advance? 

If you plan on making these vegetarian sliders for a party, you can make the filling up to 3 days in advance and the fry sauce up to 1 week in advance. When you’re ready to serve, simply reheat the filling in a skillet and then assemble the sliders as instructed. 

What to Serve with Veggie Sliders

To make the portobello sliders a meal, serve them with one or more of the following sides: 

Grilled Mexican Corn  Crispy Parmesan Ranch Potatoes Grilled Vegetables Tropical Fruit Salad Broccoli Salad Homemade Seasoned Fries

Tips for the Best Vegetarian Sliders

Have patience when cooking the mushrooms and onions. The filling takes about 20 minutes total to cook — do not crank up the heat to save time as that will result in a less rich filling.  However, you can always pop the lid on your skillet to safely speed up the cook time. That’s what I did!  Leftover fry sauce is delicious slathered on wraps and sandwiches, and can also be used as a dipping sauce.   

More Party Sliders Recipes: 

Ham and Cheese Sliders — Baked juicy ham and Swiss nestled in soft Hawaiian rolls and brushed with a buttery Dijon, onion, and poppy seed topping! Fast, easy, and a party favorite! Tried this recipe? Leave a review! Consider leaving a 5 star rating if you’ve made and loved one of my recipes!

Pepperoni Pizza Sliders — Pizza by way of supremely cheesy sliders!! EASY, ready in 15 minutes, and perfect for parties because everyone LOVES them! Totally IRRESISTIBLE!!

Ranch Chicken and Swiss Sliders — Tender chicken coated in ranch, nestled in soft rolls with Swiss and a buttery Dijon topping! Fast, easy, and everyone loves them! Perfect for parties, game days, and snacks!

Beer and Bourbon Barbecue Chicken Sliders – Chicken is cooked with beer and bourbon before being soaked in bbq sauce! So juicy, flavorful, easy, and ready in 25 minutes!

Hawaiian Ham and Swiss Sliders — Grilled pineapple slices brushed with a soy and ginger marinade add a Hawaiian-inspired twist to these irresistible sandwiches! Juicy ham, melted Swiss cheese, and melted butter are impossible to resist!

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