Created by breezermom on February 13, 2016
Step 1: Rub the tenderloins with salt and pepper; place in a 13 x 9 x 2 inch dish. Sprinkle with the garlic. Arrange the onion around the tenderloins.
Step 2: Combine 1 tablespoon butter, oil, and rosemary; drizzle over the tenderloins and onion. Insert a meat thermometer into the thickest part of 1 tenderloin.
Step 3: Bake at 325 degrees for 45-60 minutes or until the thermometer registers 170 degrees. Transfer the tenderloins and onion to a serving platter, reserving drippings in dish. Set aside and keep warm.
Step 4: Add water to the drippings; cook over high heat, deglazing the pan by scraping particles that cling to the bottom. Stir in wine.
Step 5: Combine 3 tablespoons melted butter and flour; stir well. Add the flour mixture to the pan; cook over medium heat, stirring constantly, until the mixture is thickened and bubbly. Add salt and pepper to taste. Serve tenderloins with the sauce.