Heat the oven to 400°F. Spread the bacon in one layer on an uncoated stainless half sheet pan and bake for 10 to 20 minutes, depending on thickness, until crisp.
Move the bacon to a plate and leave all rendered fat on the pan.
Toss the cauliflower in the bacon fat with 1 teaspoon sea salt and optional black pepper. Move the coated cauliflower to a large bowl, scraping excess fat back toward the pan.
Spread the chicken across the pan, roll each piece lightly in bacon fat, set skin-side up, and season with the remaining 1 teaspoon sea salt and optional pepper.
Reduce the oven to 375°F and roast the chicken for 30 minutes, until the skin begins to turn golden.
Raise the oven to 400°F. Move the chicken to one side of the pan and spread the reserved cauliflower in one layer on the other side. Scrape any fat left in the bowl over the chicken.
Roast for about 22 minutes, until cauliflower edges are caramelized and every chicken piece reaches at least 165°F in the thickest part without touching bone.
Add scallion whites and optional aged cheese over the cauliflower. Reduce the oven to 200°F and bake for 5 minutes, just until the cheese melts and whites soften.
Chop the cooled bacon. Transfer chicken and cauliflower to a platter and top the cauliflower with bacon, scallion greens, and plenty of fresh thyme leaves. Rest the chicken briefly before serving.