Guinness-Marinated Beef Tenderloin with Guinness Demi Glacé and Herb & Garlic Roasted Veggies

#AD Family-Style Holiday Celebrations Are All About The Perfect Roast. This Guinness-Marinated Beef Tenderloin with Guinness Demi Glacé and Herb & Garlic Roasted Veggies is Absolutely Incredible. Creamy, Malty, Irish-Marinated Deliciousness served with a Rich Guinness Demi and Seasonal Veggies. Yes Please! A Perfect Way to Celebrate This Holiday Season. Recipe Link in Profile. Slainté, Friends. #GuinnessUS

 Guinness-Marinated Beef Tenderloin with Guinness Demi Glacé and Herb & Garlic Roasted Veggies 

Makes 6 – 8 servings 

Guinness Marinated Beef Tenderloin 

1 X 4-pound beef tenderloin, trimmed & tied 

1 X 14.9-ounce can Guinness Draught 

¼ cup balsamic vinegar 

1 tablespoon Worcestershire sauce 

8 garlic cloves, minced 

2 shallots, minced 

3 tablespoons packed dark brown sugar 

Zest of 1 lemon, grated on a microplane

2 tablespoons chopped fresh rosemary leaves

2 tablespoons chopped fresh thyme leaves 

2 tablespoons olive oil 

Sea salt & freshly cracked black pepper 

Guinness Demi Glace 

2 tablespoons butter 

1 ½ tablespoons all-purpose flour 

½ medium onion, diced 

1 large carrot, diced 

2 celery stalks, sliced 

1 bay leaf 

10 peppercorns 

8 parsley stems 

1 X bottle Guinness Imperial Stout 

4 cups beef stock 

Sea salt 

Herb & Garlic Roasted Root Vegetables 

1 ½ pounds carrots, sliced (or halved if on the smaller side)

1 ½ pounds parsnips, halved 

1 ½ pounds small fingerling potatoes, halved 

3 garlic cloves, minced 

1 tablespoon chopped fresh rosemary leaves 

1 tablespoon chopped fresh thyme leaves 

2 tablespoons olive oil 

Sea salt and freshly cracked black pepper 

1. First, marinade your beef tenderloin. In a bowl, combine Guinness Draught, balsamic vinegar, Worcestershire, garlic, shallots, sugar, zest, and herbs, and season with a good pinch of salt and pepper. Whisk to combine, then add your beef. Cover and chill in the fridge for about 8 hours (or overnight), turning the beef a few times throughout the marinating process. Remove beef from the marinade and transfer to a large baking sheet with a wire rack. Drizzle over the olive oil, season with an extra pinch of salt and pepper, then bring to room temperature (about 1 hour before cooking). Perfect. 

2. Preheat an oven to 425 degrees F. Line a very large (or 2 medium) sheet pans with parchment paper. 

3. Next, prepare the Guinness Demi Glace. Heat a Dutch oven (or large saucepan) over medium-heat, and add the butter. When melted, add the onion, carrot, and celery, season with a pinch of salt, and saute until softened and translucent (6 – 8 minutes). Add the flour and garlic, and cook, stirring constantly, for 1 minute. Whisk in the Guinness Draught and beef stock, then add the bay leaf, peppercorns, and parsley, and bring to a gentle simmer. Let the demi bubble and  simmer away and reduce for about an hour, or until glossy and the sauce coats the back of a wooden spoon. Run through a sieve to remove the veggie bits and bobs, and transfer to a bowl for serving. Delicious! (Note! This can be done in advance, and kept in an airtight container in the fridge for up to 2 weeks) 

3. While the demi glace is bubbling away, cook the beef. Transfer the prepared baking sheet to the preheated oven and cook for about 45 – 50 minutes, or until the beef reaches an internal temperature of 130℉ (for medium-rare doneness). A meat thermometer is your best bet here, friends, and necessary to ensure perfectly cooked tenderloin. Remove beef from the oven and let stand for at least 15 minutes before carving. 

4. Lastly, while the beef is cooking, prepare your roasted root vegetables. Place the sliced carrots, parsnips, and fingerling potatoes on the prepared baking sheet, then drizzle over the olive oil, add the herbs, and season well with salt and pepper. Toss to combine, then roast for about 35 – 40 minutes, or until the veggies are fork tender and nicely caramelized. Awesome. 

5. Carve your tenderloin into ½-inch rounds, then serve with your roasted veggies and demi glace. Delicious!