Hi there, welcome on Hikashop
I think the best way to do your business is to set, as you said, the flavor as the product.
Then, you can use the variant option to create as much variant as you need.
In this case, create a new characteristic named "package size".
Then, add this characteristic to your products (for example cookie "A") and Hikashop will generate a variant for each type of package.
You then just have to edit these variants to give them the right price.
I hope it will fit your needs, to not hesitate to ask if you have any questions and send us your website link when you're finished!
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