Preheat your oven to 450°F (230°C) and line a large baking sheet with parchment paper for easy cleanup.
In a large bowl, pour the buttermilk over the cauliflower florets. Let them soak for about 30 minutes to tenderize and enhance flavor.
While the cauliflower is soaking, prepare the breadcrumb mixture. In a separate bowl, combine the panko breadcrumbs, grated Parmesan cheese, ranch seasoning mix, garlic powder, onion powder, smoked paprika, salt, and pepper. Mix well.
Once the cauliflower has soaked, remove the florets from the buttermilk and allow any excess liquid to drip off.
Dredge each cauliflower floret in the flour, shaking off the excess. Next, dip it back into the buttermilk, allowing it to soak again briefly, and then coat it in the breadcrumb mixture. Press lightly to adhere the mixture to each floret.
Place the coated cauliflower florets on the prepared baking sheet, ensuring they are spaced evenly apart for maximum crispiness.
Lightly spray the tops of the florets with olive oil to help them achieve a golden and crispy texture while baking.
Bake in the preheated oven for 25-30 minutes, or until the cauliflower is golden brown and crispy, flipping them halfway through the cooking time.
Once baked, remove from the oven and let cool for a couple of minutes. Garnish with fresh parsley before serving.
Serve hot as a snack, appetizer, or side dish, and enjoy the delicious burst of ranch and parmesan flavors!