This stuffed pork tenderloin recipe is one of my favorite dinner party recipes, and is also great to make for special occasion dinners. It's a convenient recipe to make as the tenderloins can be stuffed 1-2 hours in advance and refrigerated (that way your kitchen isn't messy when guests arrive!) If you do make them and refrigerate them in advance you will need to increase the cooking time by about 10 minutes or so. You may not see this stuffed pork tenderloin recipe in the weekly menus on this site but I'm posting it in case you are looking for an entree to make for a special occasion.
4 Tablespoons butter
4 green onions, diced
1 medium yellow onion, diced
4 stalks celery, diced
1 1/2 cups breadcrumbs (either fresh or prepared)
1/4 teaspoon Old Bay seasoning
1/4 teaspoon ground black pepper
1.5 - 2 pounds pork tenderloin
2 Tablespoons flour
2 garlic cloves, minced
1 cup sliced mushrooms
1/4 cup cognac
2-3 cups beef broth
roasting twine is needed for this recipe
Melt 2 Tablespoons of butter and saute the green onions, 1/2 of the yellow onion, and the celery. Remove from heat. Add the breadcrumbs and seasoning and cool. Slice the tenderloins lengthwise without cutting all of the way through. Fill the tenderloins with the suffing mixture and secure with roasting twine (see cook's notes). Place the stuffed tenderloins on a rack in a 2" high baking pan.
Make the cognac sauce by melting the remaining butter and mixing in the flour. Saute the remaining 1/2 of yellow onion, garlic, and sliced mushrooms in this roux (butter/flour mixture). Add the cognac and 1 cup of beef broth and stir and continue to cook over medium low heat until the mixtures are fully combined and thickened. Pour this gravy over the tenderloins in the pan. Bake, uncovered, at 350'F for 60-90 minutes, or until the tenderloins reach an internal temperature of 160'. Baste with pan drippings and the other can of beef stock.
Slice the tenderloins and serve with the pan gravy. If desired the pan gravy and also be thickened by melting 1 Tablespoon butter and mixing in 1-2 Tablespoons flour. When combined add pan drippings and stir well. Add additional broth if needed to reach the desired thickness. Season as needed before serving.
Cook's notes: If you want to get really fancy you can use wilted green long onion stems or extra long chives to secure the tenderloins instead of twine. To wilt these just boil them for 30-60 seconds until they are soft. Blot them dry and use them instead of string. I usually grow chives in my garden in the summer for this purpose as home grown chives can grow very long