Preheat your oven to 425°F.
Wash and dice the red potatoes into bite-sized pieces. Toss them in a bowl with half a tablespoon of olive oil, minced garlic, a little salt, and pepper.
Spread the potatoes out on a baking sheet lined with parchment paper, and roast in the preheated oven for about 20-25 minutes, or until they are crispy on the outside and tender inside. Toss halfway through the cooking time.
While the potatoes are roasting, prepare the asparagus by trimming the woody ends. Drizzle lightly with a tiny bit of olive oil (optional) and season with salt and pepper.
Heat a non-stick skillet over medium-high heat. Season the beef sirloin with salt, pepper, and a sprinkle of finely chopped rosemary. When the skillet is hot, add the steak.
Sear the steak for about 3-4 minutes on each side, or until it reaches your desired level of doneness.
Once the steak is cooked, let it rest for a couple of minutes before slicing.
Plate the sliced steak with a serving of roasted potatoes and tender asparagus. Enjoy your balanced, flavorful meal!