Heat 1 tbsp oil in large skillet over med-high + sauté half the spinach + salt/pep 1-2 min until wilted; add remaining spinach + cook 1-2 min more til all spinach is wilted; set aside

Heat lightly oiled skillet over med-high; pat chicken breasts dry + sear 2 min per side til warmed through

Meanwhile, pour contents of mashed cauliflower into a microwavable-safe dish + cover with a damp paper towel; cook high 1-2 min until hot; divide all to plates + drizzling dressing on chicken