Mushroom Bourguignon

For the stew

• 10 ounces pearl onions, peeled
• 2 tablespoons olive oil
• 1 tablespoon butter
• 2 pounds portobello mushroom caps, sliced
• 1 pound brown or shiitake mushrooms, sliced
• 2 carrots, diced
• 1 fennel bulb, diced
• 6-8 garlic cloves, minced
• 1 1/2 cup red wine
• 2 tablespoons tomato paste
• 2 cups vegetable broth
• 1/2 teaspoon dried basil
• 1/2 teaspoon dried thyme

Finishing touches

• 2 tablespoons softened butter, olive oil, or a combination
• 3 tablespoons all-purpose flour
• Juice of 1/2 lemon
• 12 ounces whole-wheat shells or other short pasta

1. Heat 1/2 tbsp butter and 1 tbsp olive oil in a large heavy saucepan or dutch oven over high heat. Add mushrooms and saute 3-4 minutes, just until they begin to darken and shrink. Remove from pot and set aside.
2. Lower heat to medium, and add the other 1/2 tbsp butter and 1 tbsp olive oil. Saute carrot and fennel for about 8 minutes, until softened. Add garlic and saute a couple minutes more.
3. Pour in wine and deglaze the pot, scraping up any delicious brown bits. Return heat to high and let the wine bubble until it reduces by half.
4. Stir in tomato paste, basil, thyme, broth, and the reserved mushrooms, along with any mushroom juice that's accumulated. Bring to boil.
5. Turn heat to low and simmer about 20 minutes, or until mushrooms are tender. Add pearl onions and simmer 5 minutes more.
6. Combine the softened butter/oil and flour with a fork, whisking to make a smooth paste. Stir the paste into the stew, then simmer 10-15 minutes, or until the stew has thickened to your liking.
7. Divide the pasta among six bowls. Stir the lemon juice into the stew, and ladle over the pasta.