Preheat your oven to 400°F and line a baking sheet with parchment paper.
Peel and dice the sweet potato into half-inch cubes, then toss them on the baking sheet with 0.5 tablespoons of olive oil, rosemary, thyme, sea salt, and black pepper.
Roast the sweet potatoes for 20-25 minutes, tossing halfway through, until they are tender and caramelized on the edges.
While the potatoes roast, whisk the whole egg and egg whites together in a small bowl until well combined.
Heat a large non-stick skillet over medium-high heat with the remaining 0.5 tablespoons of olive oil and sear the sirloin steak for 3-4 minutes per side until a golden crust forms.
Remove the steak from the pan to rest, then lower the heat to medium-low and pour in the egg mixture, scrambling gently until fluffy and just set.
Slice the rested sirloin and assemble the bowl by dividing the roasted sweet potatoes, steak, and scrambled eggs. Garnish with freshly chopped chives and sliced avocado to serve.