Beef Tenderloin Sandwiches with Norton-Shiitake Sauce

Ingredients

1. 1 stick unsalted butter, cut into tablespoons
2. 6 garlic cloves, minced
3. 4 scallions, minced
4. 1 1/2 pounds shiitake mushrooms, stemmed, caps thinly sliced
5. 1 1/2 teaspoons chili powder
6. 1 1/2 teaspoons dried thyme
7. Coarsely ground black pepper
8. 2 cups beef stock or low-sodium broth
9. 2 cups Missouri Norton or other dry red wine
10. 1 tablespoon soy sauce
11. 1 teaspoon cornstarch dissolved in 1 tablespoon cold water
12. Salt
13. 2 baguettes
14. 2 pounds filet mignon, sliced 1/2 inch thick
15. Extra-virgin olive oil, for brushing

1. In a large, deep skillet, melt 4 tablespoons of the butter. Add one-third of the minced garlic and all of the scallions and cook over moderately high heat for 1 minute. Add the shiitakes and cook until slightly softened, about 2 minutes. Add the chili powder, thyme and 1 teaspoon of pepper and cook over moderate heat, stirring occasionally, until the shiitakes begin to brown, about 5 minutes. Add the stock, wine and soy sauce and bring to a boil. Simmer gently until reduced to 1 cup, about 40 minutes. Stir the cornstarch slurry and whisk into the liquid. Cook, stirring, until slightly thickened, about 2 minutes. Season with salt; keep warm.
2. Preheat the broiler. Cut the baguettes into thirds and split the pieces lengthwise, taking care not to cut all the way through. In a small saucepan, melt the remaining 4 tablespoons of butter. Add the remaining minced garlic and cook over low heat until fragrant, about 4 minutes. Brush the garlic butter on the baguettes and sprinkle lightly with salt. Broil the bread, cut side up, for about 1 minute, until golden.
3. Preheat a grill pan. Brush the tenderloin slices with oil; season with salt and pepper. Grill the meat in batches over high heat, turning once, until charred and medium-rare, about 5 minutes. Dip the meat in the mushroom sauce and arrange on the baguettes. Spoon the mushroom sauce on top, close the sandwiches and serve.