(Here's a re-post from 2006 to help beat the hot weather- Steve)
I had a similar plate in Mexico City this last Spring and Paula Wolfert has a close version in her book The Slow Mediterranean Kitchen
It
works as a light dinner or an appetizer plate. The ingredients are
canned sardines, sliced avocado, large white runner beans in a simple
vinaigrette, thin red onion rings, pickled jalapeno
peppers and a small stack of mini tortillas. You could also use good
tortilla chips or even bread.
If you find a good brand of domestic sardines, let me know. The
European sardines always seem to be packed in better oil.