Preheat the oven to 425°F for roasting the vegetables.
Wash the sweet potato and cut it into 1/2-inch cubes. Toss with a bit of olive oil, salt, and pepper.
Spread the sweet potato cubes on a baking sheet and roast in the oven for 20-25 minutes until tender and lightly caramelized.
Meanwhile, trim the ends of the green beans. Toss them lightly with salt, pepper, and a drizzle of olive oil and add them to the baking sheet during the last 10 minutes of roasting.
Pat the lean beef sirloin steak dry with a paper towel and season generously with salt and pepper on both sides.
Heat a skillet over medium-high heat and add the teaspoon of olive oil. Once the oil is shimmering, place the steak in the skillet.
Sear the steak for about 3-4 minutes on each side for medium-rare, or adjust time to your preferred doneness.
Remove the steak from the skillet and allow it to rest for a few minutes before slicing against the grain.
Plate the sliced steak with a serving of roasted sweet potato and green beans. Enjoy your balanced, nutrient-packed dinner!