3 tablespoons extra virgin olive oil
2 pounds beef stew meat, cut into 1-inch cubes
1/3 cup all-purpose flour
1/2 teaspoon kosher salt
1/2 teaspoon ground black pepper
1 tablespoon Worcestershire sauce
1 tablespoon Dijon mustard
2 teaspoons minced garlic
1 teaspoon dried rosemary
1/2 teaspoon dried thyme
4 carrots, peeled and sliced
3 medium potatoes, peeled and cubed into bite-sized pieces
2 stalks celery, sliced
1 yellow onion, chopped
2 1/2 cups beef-flavored or chicken broth
1 1/2 cups (12 ounces) dark beer (or substitute additional broth)
Heat half of the olive oil in a large, deep skillet over medium high. Place meat in a large bowl and sprinkle with the flour, salt and pepper. Toss to coat.
Place half of the meat in the skillet and brown, not disturbing the meat too often, turning and continuing to cook until most sides are brown. Set the first batch aside to a plate.
Heat the remaining olive oil in the skillet, brown the rest of the meat, then transfer both batches to a 6-quart or larger slow cooker.
In a small bowl, stir together the Worcestershire, mustard, garlic, rosemary, and thyme. Drizzle over the beef. Add the carrots, potatoes, celery, and onions to the slow cooker, then pour the broth and beer over the top.
Cover and cook on Low for 10 to 12 hours or High for 4 to 6 hours.