Start by bringing a pot of salted water to a boil. Add the cauliflower florets and cook for about 3-4 minutes until just tender but still crisp. Drain and set aside.
In a large skillet, heat the olive oil over medium heat. Add the sliced mushrooms and sauté for about 5-7 minutes until they are golden brown and have released their moisture.
Once the mushrooms are cooked, add the minced garlic to the skillet. Sauté for an additional 1-2 minutes until the garlic is fragrant, being careful not to burn it.
Add the blanched cauliflower florets to the skillet. Stir to combine with the mushrooms and garlic. Season with salt, black pepper, and thyme. Cook for another 5-7 minutes, stirring occasionally, until the cauliflower is heated through and slightly caramelized.
Remove from heat and sprinkle with fresh parsley. If desired, add a squeeze of lemon juice for extra flavor.