In a large stock pot, heat oil over medium heat.
Add onion and sautee until softened about 6 minutes.
Add potato, thyme, cumin, salt and pepper. Cook & stir continually for 1 minute until well coated.
Stir in broth and asparagus. Bring to a boil.
Reduce heat, cover and simmer until vegetables are tender about 20 minutes.
Stir in evaporated milk and season to taste with salt & pepper. Cook for 5 minutes until heated through.
Pour soup into a blender, in batches if needed, and puree. (an immersion blender can be used in the pot).
Ladle into serving bowls or tureen and serve with sour cream.
Enjoy.
