- 4 tablespoons (1/2 stick) unsalted butter
- 1/2 cup plus 1 tablespoon chopped shallots
- 1/2 cup dry white wine
- 2 cups chicken stock or canned low-salt chicken broth
- 1 cup beef stock or canned beef broth
- 1 12-ounce russet potato, peeled, grated, drained well
- 1/2 cup fresh white breadcrumbs made from French bread
- 2 tablespoons chopped fresh parsley
- 3 tablespoons olive oil
- 2 6-ounce beef tenderloin steaks (about 1 inch thick)
- 1 tablespoon coarse-grained mustard
- Melt 2 tablespoons butter in heavy medium saucepan over medium-high heat. Add 1/2 cup shallots and sauté 4 minutes. Add wine and boil 1 minute. Add both stocks and boil until reduced to 2/3 cup, about 28 minutes. (Sauce can be prepared 1 day ahead. Cool slightly. Cover and refrigerate.)
- Preheat oven to 200°F. Mix potato, breadcrumbs, 1 tablespoon parsley and remaining 1 tablespoon shallots in medium bowl. Sprinkle with salt and pepper.
- Heat 2 tablespoons oil in large nonstick skillet over medium heat. Mound potato mixture in skillet in 2 portions, dividing evenly. Using metal spatula, press each into 5-inch oval. Cook until bottom is brown and crisp, about 10 minutes. Turn and cook until second side browns, about 5 minutes. Transfer galettes to baking sheet. Keep warm in oven.
- Heat 1 tablespoon oil in heavy medium skillet over medium-high heat. Sprinkle steaks with salt and pepper. Add to skillet; cook to desired doneness, about 4 minutes per side for medium-rare. Transfer steaks to plate (do not clean skillet). Add sauce to skillet and bring to boil, scraping up browned bits. Mix in mustard. Remove from heat. Add remaining 2 tablespoons butter and whisk just until melted.
- Place potato galettes on plates. Top each with 1 steak. Spoon sauce over. Sprinkle with remaining 1 tablespoon parsley and serve.