2 (6-ounce) packages sliced Portobello mushrooms, cut into fourths
1 teaspoon fresh thyme leaves
3/4 teaspoons salt, divided
1/2 teaspoon pepper, divided
2 teaspoons cornstarch
1 cup vegetable broth
1/3 cup dry sherry or dry white wine
1 teaspoon Worcestershire sauce
3 1/2 cups water
1 cup quick-cooking polenta (such as Buitoni)
1 (6-ounce) package baby spinach (about 4 cups)
1/3 cup (1.3 ounces) grated fresh Parmesan cheese
1 tablespoon yogurt-based spread (such as Brummel and Brown)
How to Make It
Heat oil in a large nonstick skillet over medium heat. Add onion and garlic; sauté 5 minutes or until tender. Add mushrooms, thyme, 1/2 teaspoon salt, and 1/4 teaspoon pepper. Cook over medium-high heat 8 minutes or until mushrooms are tender, stirring frequently. Combine cornstarch, broth, sherry, and Worcestershire sauce; stir well. Add cornstarch mixture to mushroom mixture; bring to a boil over medium-high heat. Cook 2 minutes or until mixture is slightly thick, stirring frequently.
Bring water to a boil in a large saucepan. Stir in polenta; reduce heat to medium, and cook 3 to 5 minutes or until thick, stirring constantly. Add spinach, yogurt-based spread, cheese, and remaining 1/4 teaspoon each of salt and pepper; stir well to combine. Remove from heat; let stand 3 minutes or until spinach wilts, stirring often. Spoon polenta onto plates and top with mushroom mixture.