excuse me the embargo has an exception for food and medicine
It's really easy you see, you just need to pass an inspection and get a written permission from the President of the US, the payment must be made in cash in US dollars before shipment and through some non-American bank, and the shipping company must go straight from a US port to a Cuban port and back with no layovers.
This is not a joke, it's what is actually written in the law.