Fill up on savory roasted veggies with this Roasted Veggie Grilled Cheese. Stuffed with pepper, onion, and mushrooms and perfect for dipping in toasty sauce.
Today we’re whipping up a classic lunch favorite: The Grilled Cheese. Only in this recipe, we’re giving it an upgrade and packing it with veggies and rich gouda! And to achieve that sought after crispiness, we’ll coat the outsides of the bread in a generous layer of mayonnaise. It’s the best way to achieve that golden glow!
But we’re not stopping there. While living in the Netherlands I picked up a love for toasty sauce. Gouda grilled cheeses and other panini-style sandwiches (“toasties”) are often served with “toasty sauce”, a flavorful blend of mayonnaise, BBQ sauce, and hot sauce and that serves as the perfect sidekick for this gouda panini!
You can use any sauce you’d like, but I definitely recommend using something to offset the crispiness and add extra savory flavor. We’re sauce people around here!
Here’s what you’ll need
The ingredients in this pepper and mushroom grilled cheese are exactly what you’d expect: lots of veggies and delicious sourdough (or multigrain) bread! For the grilled cheese you’ll need:
- Red Bell Pepper: Roasted bell peppers are a must on any vegetable panini. You can use red, green, yellow, or orange!
- Sliced Mushrooms: As far as mushrooms go, you can use brown, white, or whatever you have on hand! You’ll need 2 cups.
- White Onion: Next up, white onion. You’ll need ½ cup, sliced.
- Bread: Bread can make or break a grilled cheese! For best results, use 4 thick slices of either sourdough or multigrain.
- Gouda: You’ll need 3 slices of gouda, as we’ll be using 1½ on each sandwich. Can’t find gouda? Cheddar, jack, or muenster also work well!
- Mayonnaise: Did you know grilled cheeses are ten times better when the outsides of the bread are coated with a layer of mayo? It helps them reach that perfect golden color!
The toasty sauce is a quick combination of mayonnaise, BBQ sauce, and optionally hot sauce. Whip it up while your grilled cheese cooks!
How to make a roasted veggie grilled cheese
This vegetable grilled cheese is made complete in just four steps. We’ll start by roasting the veggies, then we’ll assemble and cook the sandwiches panini-style.
Step 1: Roast the vegetables
Preheat the oven to 400°F (204°C). Slice the pepper, mushrooms, and onion, and throw everything onto a large rimmed baking sheet. Drizzle with olive oil and sprinkle with salt and pepper, tossing to evenly coat. Bake for 15 minutes, or until the vegetables are soft.
Step 2: Prepare the toasty sauce
While the veggies cook, mix together all of the toasty sauce ingredients (mayo, BBQ sauce, and hot sauce).
Step 3: Assemble
Build two separate sandwiches by layering 1 slice of cheese, a heap of roasted vegetables, and ½ slice of cheese atop the bread. Spread mayonnaise on the outsides of the bread.
Step 4: Cook the sandwiches
Finally, cook the sandwiches in a skillet over medium heat, or in a panini press. Cook until the outsides are golden brown and the cheese has melted. Serve immediately with the toasty sauce for dipping.
Grilled cheese variations
In the mood to mix things up? Here are some ways that you can switch up your vegetable grilled cheese.
- Swap the Pepper: Any mild pepper works well here, to include green bell pepper, poblano, or anaheim.
- Red Onion: This recipe calls for white onion, but you can also use red! You can spice things up by using caramelized or pickled onions too.
- Pepper Jack Cheese: Though this sandwich isn’t a gouda panini without the gouda, it would also taste great with pepper jack (or even a pepper jack and cheddar combo). (Or check out our full list of best cheeses for grilled cheese 👈)
- Sauces: Toasty sauce is the best for this sandwich, but you can use whatever you’d like! Blue cheese, ranch, and even plain hot sauce all taste great.
More grilled cheeses and paninis to devour
Because you can never have too many jam packed loaded sandwiches, here are four more of my favorites! Each recipe presents unique flavor pairings like blueberry x balsamic and strawberry x avocado.
- Strawberry Avocado Grilled Cheese
- Buffalo Tempeh Sandwich
- Pressed Eggplant Sandwiches
- Roasted Chickpea Gyros
- Tomato Pesto Caprese Panini
- Chickpea “Tuna” Melt
- 1 red bell pepper sliced
- 2 cups sliced mushrooms brown, white, or whatever you have on hand
- ½ cup sliced white onion
- 1 Tbsp olive oil 15 mL
- Pinch salt and pepper
- 4 thick slices bread sourdough or multigrain are best
- 3 slices Gouda cheese
- 2 Tbsp mayonnaise
- 1 Tbsp mayonnaise 15 g
- 1 Tbsp BBQ sauce 15 g
- Splash of hot sauce optional
- Roast: Preheat oven to 400°F (204°C). Slice pepper, mushrooms, and onion. Throw onto a large rimmed baking sheet. Drizzle with oil and sprinkle with salt and pepper, tossing to evenly coat. Bake for 15 minutes, or until veggies are soft.
- Sauce: Meanwhile, Mix together all Toasty Sauce ingredients.
- Assemble: Build two sandwiches by layering 1 slice of cheese, a heap of roasted veggies, and ½ slice of cheese. Spread mayonnaise onto the outsides of the sandwich.
- Cook: Cook over medium heat in a large skillet or panini press until outsides are golden brown and cheese has melted. Serve immediately with Toasty Sauce for dipping!