Ingredients...
- 1 pound cremini mushrooms, halved
- 1 tablespoon extra-virgin olive oil
- 1 large sweet onion, diced
- 1 3/4 cups light beer (drink what's left in the bottle)
- Kosher salt
- 1/3 cup finely chopped walnuts
- 1 small green bell pepper, seeded and diced
- Freshly ground black pepper
- 1/2 teaspoon chipotle chile powder
- 1/4 cup ketchup
- 3 tablespoons tomato paste
- 6 whole grain hamburger buns
- Shredded red cabbage or lettuce, pickled jalapeno and scallions, for serving, optional
