In a mixing bowl, combine softened unsalted butter, minced garlic, Dijon mustard, and lemon juice, stirring until well blended. Add fresh parsley, chives, paprika, red pepper flakes, salt, and black pepper, ensuring all ingredients are evenly incorporated into a smooth mixture.

For added depth of flavor, preheat a skillet over medium-high heat and sear the steak for 2-3 minutes on each side until a golden crust forms. Set the seared steak aside once done.

In your slow cooker, begin by layering halved baby potatoes at the bottom. Next, place the steak on top of the potatoes.

Generously spoon the prepared cowboy butter mixture over the steak and potatoes, ensuring an even coating.

Pour the beef broth around the sides of the slow cooker, avoiding direct contact with the meat.

Cover the slow cooker and set it to cook on LOW for 6-8 hours or HIGH for 3-4 hours.

If desired, mix 1 tablespoon of cornstarch with 1 tablespoon of water to create a slurry, stir it into the slow cooker during the last 30 minutes of cooking.

Once cooked, carefully transfer the steak and potatoes to a serving platter. Drizzle the flavorful sauce generously over the top and garnish with fresh parsley before serving.