Peel and dice the russet potatoes into small, even pieces. Chop the onion finely and mince the garlic.
In a large pot, melt the butter over medium heat. Allow it to foam slightly.
Add the chopped onion and sauté for about 5 minutes until translucent.
Add the minced garlic and cook for an additional 1-2 minutes until fragrant.
Incorporate the diced potatoes and stir well to coat them with the onion and garlic mixture.
Pour in the vegetable broth, ensuring the potatoes are fully submerged. Bring to a gentle boil, then reduce heat to low and cover. Simmer for about 20 minutes or until fork-tender.
Use a potato masher to mash the potatoes slightly in the pot for a creamy texture.
Stir in the heavy cream and mix well.
Season with salt and pepper, adjusting to taste.
Let the soup simmer for another 5-10 minutes on low heat, stirring occasionally.
Ladle the soup into bowls and garnish with chopped chives.
Notes
For variations, consider adding smoked paprika, vegetables, or cheese. Serve with crusty bread or a salad.