He has also been charged with the attempted murder of a second victim the following day.
Police said a surveillance camera captured video of the shooting at La Chapina Bakery on Edinger Avenue.
They say Lopez walked in and shot 22-year-old Alejandro Sanchez several times in the back while he poured coffee at the counter.
Peña is due to be arraigned on Wednesday.
A second suspect in the deadly bakery shooting is still outstanding.
If you have any information, you're asked to call Santa Ana police at (714) 245-8390.