Peel and dice the potatoes.
Chop the onion and mince the garlic.
In a large pot, melt the butter over medium heat.
Add the chopped onion and sauté until translucent.
Stir in the minced garlic and cook for an additional minute.
Add the diced potatoes to the pot.
Pour in the broth, bringing it to a boil.
Reduce heat and simmer until the potatoes are tender.
Use an immersion blender to puree the soup until smooth.
Stir in the heavy cream and season with salt and pepper to taste.