In a large Dutch oven over medium heat, warm 2 tablespoons of olive oil. Add the mild Italian sausage and bacon, cooking until browned and crispy, about 8 to 10 minutes. Remove the meat and leave some grease for flavor.

In the same pot, add diced onion and sauté until soft and translucent, about 3 to 4 minutes. Introduce minced garlic and stir until fragrant, roughly 1 minute.

Incorporate cauliflower florets into the pot and pour in enough chicken broth to cover the vegetables. Season with salt and pepper and bring to a gentle simmer for about 15 minutes until the cauliflower is tender.

Using an immersion blender, puree the soup directly in the pot until smooth and creamy. Alternatively, blend in batches.

Lower the heat to medium-low, mix in the half and half, and add back the cooked sausage and bacon with the curly kale. Simmer until the kale wilts, about 5 minutes.

Taste and adjust the seasoning with salt or pepper if needed. Serve hot, topped with optional red pepper flakes.