I know some local Hawaiian places like Matsumoto make their own "homemade" shave ice syrups. I was wondering how you could do this. I'm not wanting a recipe, but more of an idea of the components and ingredients that would go into making your own homemade syrup. I have recently ordered some commercial syrups that I should be arriving soon and I really want to experiment so I can get flavors closest to what I remember from Hawaii.

The best way is to trial and error. Stores like Matsumoto has a formula passed down for many years which is refined many times to produce that great taste. You would need to do some sampling with perhaps flavor blending as well as adding other ingredients to it to produce your own unique taste. Hope this helped.