Extracting business logic out from the code

I am using Java 8 on the server side. I have at some places some protocols or custom rules that I think do not belong to the code and should be extracted out. e.g.

There is a function which makes coffee for you. Now there can be multiple types of coffee say A, B, C and depending on the chef you may have different ways to prepare say X, Y, Z. The fundamental blocks of boiling water or arranging milk will be same though.

Now I would prefer to have ability to add new types of coffee just through adding a new file say XML one and if I want to change the preparation of coffee C then I just need to change the XML.

Therefore, I am making it a command like language of my own in some sense. I want you to help me with your views and suggestions on this approach and direct to some of the good practices and examples around it. One of the idea apart from good organization of the code is to reduce the number of deployments.