Preheat the oven: Set to 375°F (190°C). Grease a 9x13-inch baking dish.

Prep the cauliflower: If using fresh, toss florets with oil, salt, and pepper. Roast on a sheet pan for 15–20 minutes until just tender. If using frozen, steam or microwave until fork-tender, then drain well.

Cook the bacon: Pan-fry until crisp. Drain on paper towels and crumble. Reserve 1–2 teaspoons of bacon fat for extra flavor if you’d like.

Make the ranch sauce: In a large skillet over medium heat, melt butter (and bacon fat if using). Add garlic and cook 30 seconds. Whisk in cream cheese, heavy cream, and sour cream until smooth.

Season: Stir in onion powder, dried dill, parsley, chives, salt, and pepper. Taste and adjust. You want it slightly saltier than usual since it will coat the chicken and cauliflower.

Add cheese: Stir in 1 1/2 cups of the shredded cheese until melted and creamy.

Combine: In a large bowl, mix chicken, cauliflower, and most of the bacon with the sauce until evenly coated.

Assemble the casserole: Transfer to the baking dish. Top with the remaining 1/2 cup cheese and the rest of the bacon.

Bake: Bake for 18–22 minutes until bubbly and lightly browned on top.

Finish and serve: Let it rest 5–10 minutes so it sets. Top with sliced green onions. Portion into meal prep containers once slightly cooled.