Ideal, but optional: Pat beef dry. Season with Salt and Pepper. Place beef on a wire rack and let sit at room temperature for 1 hour.
Prep Onions, the Large carrot, Celery, and get rest of ingredients in base recipe out.
Melt butter in Dutch oven over medium heat.
Add onions, stirring occasionally, until softened and beginning to brown, 8-10 minutes.
Add carrot and celery. Continue to cook, stirring occasionally, for 5 minutes.
Add garlic cloves and cook until fragrant, about 30 seconds.
Stir in 1 cup broth, 1/2 cup dry red wine, 1 tablespoon tomato paste, bay leaf, and 1 sprig fresh thyme. Bring to simmer.
Move everything from dutch oven to slow cooker and carefully wipe dutch oven with paper towel to remove whatever’s left (doesn’t have to be perfect.)
Bring heat up to medium-high. Add oil to dutch oven and heat until shimmering.
Add beef and brown. Move beef to slow cooker on top of vegetables.
Add ¼ wine and ¼ broth to dutch oven and scrape up brown bits as much as possible. Drain into slow cooker.
Meat will have to cook for 9 to 10 hours on low or 6 to 7 hours on high. Turn meat over halfway through, if doing variation, this can be done after 7.5 hours (low) or 4.5 hours (high) when adding vegetables.
Transfer roasts to carving board and tent loosely with foil.
Remove and discard bay leaf and thyme sprig.
Remove root vegetables and set aside.
Transfer vegetables and liquid to blender.
Let liquid sit for 5 minutes, then skim fat.
Blend until smooth, about 2 minutes.
Transfer sauce to medium saucepan and bring to simmer over medium heat. Stir 1/4 cup dry red wine and Parsley.
If using fresh thyme add 1/4 teaspoon chopped fresh thyme. If using vinegar, add to gravy and
season with salt and pepper to taste.
Meanwhile, remove twine from roasts and slice against grain into 1/2-inch-thick slices. Transfer meat to serving platter.
Transfer large pieces of carrot, parsnip and potato to serving platter using slotted spoon, cover tightly with aluminum foil, and proceed with recipe at Step 12.
Spoon half of gravy over meat; pass remaining gravy separately.
Root Vegetables Variation
Ingredients:
1 lb Carrot, peeled, cut into 2” pieces
1 lb Parsnips
1.5 lb (Russet) Potatoes, peeled, quartered
After meat has been cooking for 7.5 hours (low) or 4.5 hours (high), take meat out temporarily and put aside. Add root vegetables and place beef back on top. Cover and continue to cook for 1.5 hours.
Things to try
Using Beef broth instead
Adaptation of the Slow-Cooker Country Style Pot Roast from ATK Cookbook, ATK Classic Pot Roast found at https://www.geniuskitchen.com/recipe/atk-classic-pot-roast-509694