Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Trim the woody ends off the asparagus and place them on the baking sheet along with the cherry tomatoes.
Drizzle the vegetables with 0.5 tablespoon of olive oil and season with half of the salt and pepper.
Roast the vegetables for 12-15 minutes until the asparagus is tender and the tomatoes have just begun to burst.
While the vegetables roast, season the chicken breast on both sides with the remaining salt, pepper, and finely chopped rosemary.
Heat the remaining 0.5 tablespoon of olive oil in a medium skillet over medium-high heat.
Place the chicken in the skillet and sear for 5-7 minutes per side, or until the internal temperature reaches 165°F.
In the final minute of cooking, add the minced garlic to the pan and sauté until fragrant, being careful not to burn it.
Remove the skillet from the heat and pour in the lemon juice and zest, swirling the pan to create a light glaze over the chicken.
Plate the chicken alongside the roasted vegetables and pour any remaining pan juices over the top before serving.