Season the sirloin steak with salt and black pepper on both sides.

Heat a skillet over medium-high heat and add 2 tablespoons of the melted garlic butter.

Once hot, add the steak and cook for about 4-5 minutes on each side for medium-rare, or until desired doneness.

Remove the steak from the skillet and let it rest for a few minutes.

In the same skillet, add the sliced zucchini and cook for about 3-4 minutes until tender.

Add the remaining melted garlic butter and toss to coat the zucchini.

Slice the steak against the grain and serve alongside the sautéed zucchini.

Drizzle any remaining garlic butter over the top and garnish with chopped parsley.