In a large pot, melt the butter over medium heat. Add the onion and garlic, and sauté until softened and fragrant, about 5 minutes.

Pour in the stock and add the diced potatoes. Bring to a boil, then reduce heat and simmer until potatoes are tender, about 15-20 minutes.

Add the shredded cabbage to the pot. Simmer for an additional 5-10 minutes, until cabbage is softened.

Using an immersion blender or regular blender, puree about half of the soup until smooth. This will thicken the broth while still leaving chunks of potato and cabbage.

Stir in the heavy cream and heat through. Season with salt and pepper to taste.

Ladle the soup into bowls. Garnish each serving with a sprinkle of sliced green onions and crispy bacon bits, if desired.

Serve hot with crusty bread for a filling and comforting meal that celebrates the flavors of traditional Irish colcannon in a cozy soup form. Enjoy this creamy, hearty taste of Ireland!