Mushroom Gravy

• 1 pound portobello mushrooms
• 1 pound cremini or button mushrooms
• 4 cup organic mushroom or vegetable stock
• 2 tablespoon unsalted butter
• 1/2 cup finely chopped yellow onion
• 1 tablespoon marsala wine (optional)
• 3 tablespoon all-purpose flour
• 1 teaspoon fresh thyme leaves

1. Remove stems from portobello and cremini or button mushrooms. Place stems and mushroom stock in a medium saucepan over medium-high heat. Bring to a boil, reduce heart to low, and simmer for 30 minutes. Strain and set aside.
2. Finely chop portobello cap and set aside. Thinly slice cremini or button mushrooms. Place 3 tablespoons butter in a large saute pan over medium heat; add onion and cook until translucent, 3 to 5 minutes. Add chopped and sliced mushrooms and cook until mushrooms are soft and browned. Add marsala, if using, and cook, stirring to loosen any browned bits on the bottom of the pan. Remove from heat and set aside.
3. Place remaining tablespoon butter and flour in a medium saucepan over medium heat; cook until lightly browned, 2-3 minutes. Slowly whisk in stock and bring to a boil whisking until thickened. Add reserved mushroom mixture and thyme.