Preheat oven to 375 degrees Fahrenheit (190 degrees Celsius) and grease a 9x13 inch baking dish.

Steam the cauliflower florets in a steamer basket over boiling water for 5 to 7 minutes until tender-crisp.

Drain the cauliflower thoroughly and pat dry with paper towels to remove excess moisture.

In a large mixing bowl, combine the sour cream, softened cream cheese, garlic powder, salt, and pepper until smooth.

Fold in the steamed cauliflower, half of the shredded cheddar cheese, half of the bacon, and half of the green onions.

Transfer the mixture to the prepared baking dish and spread evenly.

Top with the remaining cheddar cheese and bacon bits.

Bake for 15 to 20 minutes until the cheese is melted and bubbling.

Remove from the oven and garnish with the remaining green onions before serving.