A portobello burger with sun-dried tomato mayo and grilled red onion makes for a "beefy" - though beef-free - burger. LARRY CROWE / THE ASSOCIATED PRESS

Whenever the word "veggie" modifies "burger," many people taste skepticism more than anything else.

While it's true that many vegetarian burgers are nothing more than mushy patties of ground-up produce, this portobello burger with sun-dried tomato mayonnaise is a burger of a different class.

Marinated and grilled just right, a large portobello mushroom cap can be just as toothsome and "meaty" as the real deal. And when you add accouterments such as char-grilled red onion and red bell pepper, plus a slathering of savory sun-dried tomato mayo, you just might turn a meat eater into a vegetarian. At least until the next meal.

Portobello Burger With Sun-Dried Tomato Mayo

Servings: 4

For the mayo:

• 1/2 cup reduced-fat mayonnaise

• 2 tablespoons prepared sun-dried tomato pesto

• 1 teaspoon lemon juice

For the burger:

• 1/3 cup red wine vinegar

• 1/4 cup extra-virgin olive oil

• 2 cloves garlic, minced

• 1 teaspoon Dijon mustard

• 1/2 teaspoon salt

• 1/2 teaspoon ground black pepper

• Four 5-inch round portobello mushroom caps

• Four 1/2-inch-thick slices of red onion, cut from a large red onion

• 1 yellow or orange bell pepper, quartered lengthwise and seeded

• 4 kaiser rolls, split

• 1 cup baby arugula

In a small bowl, stir together the mayonnaise, sun-dried tomato pesto and lemon juice. Cover and refrigerate until serving time.

In a large bowl, whisk together the vinegar, oil, garlic, mustard, salt and pepper. Add the mushrooms, onions and peppers, turning to coat with the marinade.

Heat a gas grill to medium-high or light a charcoal fire.

Remove the vegetables from the marinade, letting any excess drip off. Reserve the marinade. Grill the vegetables until they're browned on both sides and tender, about 5 minutes per side, brushing once with additional marinade during cooking.

Meanwhile, toast the rolls at the edge of the grill or in a toaster.

To assemble the burgers, divide the arugula among the 4 roll bottoms. Top with onions and peppers. Set the mushroom caps on top. Spread a quarter of the mayo on each roll top and set on top of the mushrooms.

Per serving (values are rounded to the nearest whole number): 430 calories; 207 calories from fat; 23 g fat (4 g saturated; 0 g trans fats); 1 mg cholesterol; 47 g carbohydrate; 9 g protein; 4 g fiber; 895 mg sodium.