In a large pot, heat olive oil over medium heat.
Add chopped onion and minced garlic; sauté until translucent.
Remove the sausage from its casing and add to the pot, breaking it apart as it cooks.
Once browned, add diced potatoes and chicken broth to the pot.
Bring the mixture to a boil, then reduce to a simmer.
Cook for about 15 minutes, or until potatoes are tender.
Add chopped kale and red pepper flakes; stir well.
Continue to simmer for another 5 minutes.
Stir in the heavy cream and season with salt and pepper.
Serve hot, garnished with extra kale if desired.