Preheat your oven to 400°F (200°C) and prepare a rimmed baking sheet.
Trim the woody ends off the asparagus spears and place them on the baking sheet.
Mince the garlic cloves and toss them with the asparagus, 0.5 tbsp of olive oil, and a pinch of the sea salt.
Spread the asparagus in a single layer and roast for 12-15 minutes until tender and slightly browned at the tips.
While the asparagus roasts, pat the chicken breast dry with paper towels and season both sides with the remaining sea salt, black pepper, and dried oregano.
Heat the remaining 1 tbsp of olive oil in a heavy-bottomed skillet or cast iron pan over medium-high heat.
Once the oil is shimmering, add the chicken breast and sear for 6-7 minutes per side without moving it, ensuring a deep golden crust forms.
Check that the internal temperature of the chicken reaches 165°F (74°C), then remove from the heat and let it rest for 5 minutes.
Serve the chicken alongside the roasted asparagus and finish the entire plate with a fresh squeeze of lemon juice.