Code for multiple product variants? (Mix and Match)

Hey, I'm currently creating a website for a Candy Store which requires a product that will allow to select X amount of flavours in a mix.

Example Variants:

• Flavours:
  • Lemon, Cherry, Apple
• Size:
  • 200g (£5), 500g (£8)

Now I would like to have a `select box` option to select multiple variants.

To make this even more complex, I would like to have an option to select how much of each flavour the person wants e.g. if they select 200g, the could have an option to select how many grams of each flavour they would want.