Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Clean the cremini mushrooms with a damp cloth to remove debris, then halve them; cut the chicken breast into uniform 1-inch cubes for even cooking.
In a large mixing bowl, whisk together the extra virgin olive oil, minced garlic, sea salt, black pepper, chopped thyme, and chopped rosemary.
Add the cubed chicken and halved mushrooms to the bowl, tossing thoroughly until every piece is well-coated with the aromatic herb oil.
Spread the mixture in a single layer onto the prepared baking sheet, ensuring there is enough space between the pieces so they roast rather than steam.
Place the sheet in the oven and roast for 18 to 20 minutes, or until the chicken is cooked through and the mushrooms have developed a rich, golden-brown color.
Remove from the oven and immediately toss the roasted mixture with fresh lemon juice and lemon zest to brighten the flavors before serving.