Preheat oven to 400°F. Cut off the top of the garlic heads and place them in a baking dish. Drizzle with olive oil and roast for 30 minutes or until soft.
In a large pot, sauté onion in butter over medium heat until softened. Add chicken broth and potatoes and bring to a boil. Reduce heat to low, cover the pot, and simmer for 20 minutes or until potatoes are tender.
Remove garlic from oven and let cool.
Once cooled, squeeze out the roasted garlic cloves into the soup pot.
Add salt, paprika, and black pepper to the soup and stir.
Using an immersion blender or potato masher, blend or mash soup until desired consistency is reached.