Preheat your oven to 400°F and line a baking sheet with parchment paper for easy cleanup.
Toss the trimmed asparagus spears with 0.5 tablespoons of olive oil, a pinch of sea salt, and black pepper on the prepared baking sheet.
Roast the asparagus for 12 to 15 minutes until they are tender and slightly charred at the tips.
While the asparagus roasts, season the chicken breast evenly on both sides with dried oregano, remaining sea salt, black pepper, and minced garlic.
Heat the remaining 0.5 tablespoons of olive oil in a large skillet over medium-high heat.
Place the chicken in the skillet and sear for 6 to 7 minutes per side, or until the internal temperature reaches 165°F.
Remove the skillet from the heat, drizzle the fresh lemon juice over the chicken, and let it rest for 3 minutes to lock in the juices.
Serve the sliced lemon-herb chicken alongside the roasted asparagus over the warm, fluffy brown rice.