Preheat your oven to 425°F.
In a large bowl, toss the cauliflower florets with olive oil, garlic powder, smoked paprika, salt, and black pepper until evenly coated.
Spread the seasoned cauliflower in a single layer on a baking sheet.
Roast in the preheated oven for 25-30 minutes, or until the cauliflower is tender and golden brown, stirring halfway through for even cooking.
Remove the cauliflower from the oven and sprinkle the shredded cheddar cheese and crumbled bacon over the top. Return to the oven for an additional 5-7 minutes, or until the cheese is melted and bubbly.
Once done, remove from the oven and garnish with sliced green onions and a dollop of sour cream before serving.