Sauté onion and bell pepper in oil in a Dutch oven or 3-quart saucepan over medium heat until onion just starts to brown, 5 to 7 minutes, stirring occasionally.
Add potato salad, beer, broth and meat, if using; stir to combine. Bring to a boil, reduce heat and simmer, uncovered, 10 minutes, stirring occasionally. Add salt, if desired, pepper and parsley.
Serve topped with rye croutons and bacon, if desired.
Notes
To chop potato salad, remove top from can, insert clean kitchen scissors into potato salad and snip until chopped.Substitute 1 can (14 ounces) chicken broth for the beer and chicken broth in the above recipe.