Begin by cutting 1 lb of beef sirloin into bite-sized pieces, about 1-inch cubes. Trim the ends off 1 lb of Brussels sprouts and slice them in half. Mince 4 cloves of garlic finely and chop fresh parsley for garnish. Having everything ready will make the cooking process smooth and fast.
Heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Once hot, add the halved Brussels sprouts cut-side down. Sprinkle with salt, pepper, and 1 teaspoon garlic powder. Let them cook undisturbed for about 5-7 minutes or until they develop a beautiful golden-brown crust. Flip and cook for another 3-4 minutes until tender but still firm. Remove from the skillet and set aside.
In the same skillet, reduce heat to medium and add 2 tablespoons of unsalted butter. When melted, add the bite-sized beef pieces in a single layer. Season with salt and pepper. Let the steak sear without moving for 2-3 minutes, then stir or flip to brown all sides evenly. The goal is a caramelized crust with a juicy center.
Once the steak is nearly cooked through, add the minced garlic directly to the pan. Stir frequently for about 1-2 minutes to infuse the garlic butter flavor and avoid burning. Return the Brussels sprouts to the skillet and toss everything together so the garlic butter coats all the ingredients evenly.
Turn off the heat and sprinkle chopped fresh parsley over the top for a fresh finish. Serve immediately while warm.
