Preheat your oven to 400°F (200°C).
Clean the mushrooms with a damp cloth and halve them if large.
In a large oven-safe skillet, heat the olive oil over medium heat. Add the garlic cloves, lightly crushed, and sauté until fragrant, about 1 minute.
Add the mushrooms to the skillet and toss to coat in the olive oil and garlic. Season with a pinch of salt and pepper.
Drizzle the unsalted butter over the mushrooms. Add the rosemary and thyme sprigs. Transfer the skillet to the oven and roast for about 15 minutes, stirring halfway through.
While the mushrooms roast, season the chicken breast with salt and pepper. Heat a grill pan over medium-high heat and cook the chicken for about 5-6 minutes per side, until fully cooked and juicy. Let rest briefly before slicing.
Once the mushrooms are done, remove them from the oven and drizzle with lemon juice. Stir in the fresh parsley.
Plate the roasted garlic butter mushrooms alongside slices of grilled chicken breast.
Serve warm and enjoy the blend of herby, buttery mushrooms with the lean protein of chicken.