Heat a skillet over medium-high heat and brown the beef stew meat in batches until it develops color on all sides. Transfer the browned beef to the slow cooker.
Add the sliced mushrooms, diced onion, and minced garlic to the slow cooker with the beef.
In a small bowl, stir together the smoked paprika, Worcestershire sauce, beef broth, tomato paste, salt, and black pepper until smooth.
Pour the broth mixture over the ingredients in the slow cooker and stir to combine everything evenly.
Cover and cook on low for 7 to 8 hours until the beef is fork-tender.
Stir the stew once more, then sprinkle with the chopped fresh parsley before serving.