Dear Odoo'ers!

We'd be very grateful for some advice on the following please:

In Odoo 13, we want to setup Product Variants for multiple selection rather than being mutually exclusive per attribute.

A good example would be pizza:

You want to be able to select as many toppings as you wish from single list.  Currently, you'd need one Attribute called Toppings, but you can then only select one of the values, e.g. mushroom, or red onions, or pepperoni - but we'd want to select multiple values, e.g. red onions and pepperoni.

Our preference is finding a way to do it without customising Odoo (even if we don't use Product Variants).  If we do need to customise it that's fine as long as it doesn't have any negative effects on other linked modules (e.g. the quote builder)

Many thanks

Dom