Heat a large cast iron pan or skillet over medium-high heat. Place the bacon in the pan, cooking until crispy, or roughly two minutes per side. Set aside.

While the bacon is cooking, heat a large soup pot or Dutch oven medium heat. Drizzle olive oil in the pot, then add the chopped onion. Add the garlic, onion salt, red chili flakes, and chives to the large pot with the onion.

When the onion is translucent, but not caramelized, add the beef bone broth. Add the cauliflower florets, and cover. Cook for 15 minutes, or until fork-tender.

While the cauliflower is simmering, prepare your garnishes. Chop the bacon and green onion.

Remove the cauliflower from heat, carefully pouring into a high-powered blender or food processor. Blend in batches, as only half the mixture will fit into your food processor at one time. Hold tightly to the lid, as the heat will cause excessive pressure while blending.

Once fully blended, return the cauliflower mixture to the soup pot, turning the burner back to medium heat. Stir in the heavy cream and bacon bits, reserving some bacon to be used as a garnish. Continue to cook for 5 minutes.

Pour soup into serving bowls. Top with bacon, green onions, cheddar cheese, and sour cream. Serve.