Grilled Portobello Mushroom Burger with White-Bean Puree

This one comes to us from Martha Stewart. When I first started to cook, I was afraid of my Martha Stewart cookbooks. The domestic goddess scared me. I don't know why I was so afraid of her recipes, it wasn't like she was in the kitchen with me looking over my shoulder and ready to scream at me because I wasn't using the freshest of ingredients. I was also afraid that her recipes were way over my head. Some of them certainly are, and I can just skip those or try them and hope for the best. This is a Martha recipe that was pretty easy to make and did not require a lot of prep work.

The other day I really wanted a hamburger and as I have given up red meat, I did not have one. This came very close to satiating my desire the the juicy deliciousness that is a hamburger. I really fear that I will breakdown this summer and have one. As of now, I have not broken down for a steak or a hamburger (we will see how long that will last).

2 large garlic cloves, minced
2 tablespoons chopped fresh thyme (I used dried thyme, and only about 2 teaspoons worth)
1 cup canned cannellini beans, drained and rinsed
2 tablespoons extra virgin olive oil
8 large portobello mushroom caps
4 teaspoons balsamic vinegar
1 large red onion
4 hamburger buns
smoked cheddar cheese (however much you want to use to top your burger off)
arugula (however much you want to use to put on your burger)

1. Heat grill over medium heat.
   
2. In a food processor, combing 1/2 teaspoon garlic, half the thyme, cannellini beans, and 1 teaspoon oil; process to form a smooth and spreadable paste. If the mixture is too thick, add 1 teaspoon water. Season with pepper, and pulse to combine. Set aside
3. Combine remaining garlic, thyme, and oil in a shallow bowl. Place mushroom caps in garlic mixture, and turn to coat. Season with pepper, drizzle with vinegar.
   
4. Place onion slices on a plate and light coat each side with cooking spray. Grill slices until undersides are lightly charred, about 3 minutes. Flip onions, and continue grilling until tender and charred on the other side, about 3 minutes more. Transfer onions to plate and keep warm.
   
5. Place mushrooms on grill, stem side up. Grill until undersides are browned and juice have begun to collect in the centers, about 5 minutes Flip mushrooms, and continue cooking until the other sides are browned and centers are tender, about 4 minutes more.
   
6. Place hamburger buns on grill; cook until warm and toasted. Transfer to plate; spread bean puree on the bottom half of each bun and top with two grilled mushroom caps. Top burgers with cheese, grilled onions, cheese, and a small handful of arugula.

Yield: 4 servings