Heat olive oil in a 4 quart saucepan until it starts to shimmer.
Add salsa to pan and cook until it bubbles and becomes fragrant, approximately 3 minutes.
Add beans and stock to pan. Bring to a boil. Reduce heat and simmer for 10 minutes.
Using an immersion blender, puree soup in the saucepan until it is smooth. Some small bits of beans may remain. You can also use a regular blender, but you will need to blend the soup in batches. Hot soup will expand in the blender, so never fill it more than halfway.
Add salt to taste and stir to blend.
Ladle into bowls and top with garnishes, if desired. Enjoy!