- 1 tablespoon extra virgin olive oil
- 1 large onion, cut into ½-inch dice
- 1 large carrot, peeled and cut into ¼-inch-thick slices
- 1 large celery rib, cut into ¼-inch-thick slices
- 1 pound cremini (baby portobello) mushrooms, cut into slices
- 1 clove garlic, finely chopped
- ½ teaspoon dried thyme
- ½ teaspoon dried rosemary, crushed
- ½ cup wild rice, rinsed
- ½ ounce dried wild mushrooms, any type, minced
- 6 cups beef broth
- 1 cup canned diced tomatoes
- 1 teaspoon kosher salt
- ¼ teaspoon coarsely ground black pepper
- 3 tablespoons instant mashed potato flakes
- 1 tablespoon chopped fresh Italian (flat-leaf) parsley
- Heat the oil in a large skillet over medium-high heat. Add the onion, carrot, celery, and cremini mushrooms and sauté until the vegetables brown lightly, about 6 minutes. Add the garlic, thyme, and rosemary and cook for another minute. Transfer to a 5- to 6-quart slow cooker.
- Add the wild rice, dried wild mushrooms, beef broth, tomatoes, salt, and pepper. Cover the cooker and cook on high for 4 hours, or on low for 6 to 8 hours, until the wild rice is tender.
- Stir in the potato flakes and parsley and cook on high for 10 minutes