Preheat the oven to 425°F.
Peel (if preferred) and dice the sweet potato into 1-inch cubes. Toss with half a teaspoon of olive oil, a pinch of salt, and black pepper. Spread the cubes evenly on a baking sheet.
Place the sweet potato in the oven and roast for about 20-25 minutes until tender and slightly caramelized.
While the sweet potato roasts, prepare the green beans by trimming the ends. Toss them with a small drizzle of olive oil, salt, and pepper, and set aside.
Heat a heavy skillet over medium-high heat. Season both sides of the 8 oz lean beef steak with salt, black pepper, and dried thyme.
Sear the steak in the heated skillet for about 3-4 minutes on each side for medium-rare, or adjust the timing to achieve desired doneness.
In the last 5 minutes of sweet potato roasting, add the prepared green beans to the baking sheet to roast alongside until crisp-tender.
Once everything is cooked, plate the seared steak alongside the roasted sweet potato and green beans. Let the steak rest for a few minutes before slicing.
Serve warm and enjoy your nutritious, balanced dinner.