Peel and dice the potatoes and onion.

Place potatoes and onion in a large pot and cover with vegetable broth.

Bring to a boil, then reduce heat and simmer for 20-25 minutes, or until potatoes are tender.

Carefully blend the soup with an immersion blender or in a regular blender (in batches).

Stir in smoked paprika and garlic powder.

Knock off the heat and add the skim milk.

Serve immediately with a dollop of low-fat sour cream, if desired.