Pat the beef cubes dry with paper towels and season with about 1 teaspoon salt and 1/2 teaspoon black pepper per side, or to taste.
In a large bowl, toss together beef cubes, halved baby potatoes, garlic powder, onion powder, and dried thyme until evenly coated.
Transfer the beef and potato mixture to a 4-6 quart slow cooker, spreading into an even layer (fill no more than two-thirds full).
In a small saucepan over low heat, melt butter completely. Stir in beef broth and Worcestershire sauce until well combined.
Pour the garlic butter mixture evenly over the beef and potatoes in the slow cooker.
Cover and cook on LOW for 6-7 hours or on HIGH for 3-4 hours, until beef is fork-tender (easily pierced and shreds with light pressure) and reaches 145°F internal temperature, and potatoes are soft all the way through.
Let rest for 5 minutes, then gently stir contents and garnish with fresh chopped parsley before serving.
Notes
For extra flavor, sear beef cubes in a hot skillet for 1-2 minutes per side before adding to slow cooker.
Create a thicker sauce by mixing 1 tbsp cornstarch with 2 tbsp cold water and stirring into slow cooker during last 30 minutes on HIGH.
Use a 4-6 quart slow cooker for best results. Don’t overcrowd – fill no more than two-thirds full for even cooking.
Use unsalted butter to better control salt levels in the final dish.
Worcestershire sauce can be substituted with equal parts soy sauce mixed with balsamic vinegar, or coconut aminos for gluten-free option.