Grilled Portobello Burgers With Creamy Dijon Sauce - cooking recipe

Ingredients

4 large portobello mushroom caps, wiped clean with a damp cloth
1 medium red onion, cut 1/4 inch slices
1 1/2 tablespoons extra virgin olive oil
4 whole wheat hamburger buns (or try whole wheat sandwich thins)
2 ounces blue cheese, crumbled (1/2 cup)
4 romaine lettuce leaves
2 tablespoons nonfat plain Greek yogurt (I use Chobani)
1 tablespoon extra virgin olive oil
2 teaspoons Dijon mustard
2 garlic cloves, minced
2 teaspoons dried basil
1 tablespoon finely chopped parsley
1/2 teaspoon sea salt

Preparation

Heat a grill pan on medium-high (or use regular grill). Lightly brush mushroom caps and onion with oil. Grill both for 4 to 5 minutes per side or until mushrooms are tender. (NOTE: Mushrooms will begin to release their juices when they are tender.) Set aside on separate plate. Grill buns, cut-sides-down, for 1 to 2 minutes per side or until toasted.
Meanwhile, prepare sauce: Combine all sauce ingredients in a small bowl. Spread sauce on bottom half of each bun, dividing evenly. Top with onion, mushroom caps, cheese and lettuce.