A: Nested modifiers are available for choices that first stem from a size choice. For all other scenarios, let's take a look at the example below:
As you can see, this item offers multiple layers of choices: choose two items, choose a protein for each. Firstly, price variances can only be sizes and quantities. So no, you should not create one item with Choose 1, Choose 2, and Choose 3 in the price variances. You'll want to split this into three items:
Gringo Combos - Choose 1
Gringo Combos - Choose 2
Gringo Combos - Choose 3
Let's look at the Gringo Combos - Choose 2.
1st layer: Which two options out of this list do you want?
2nd layer: Now that you've chosen two items, do you want chicken, ground beef, or shredded beef for the first item?
3rd layer: Now that you've chosen two items, do you want chicken, ground beef, or shredded beef for the second item?
This first choice is pretty easy to turn into an extra with five options and a min/max of 2. At minimum the customer must choose two options, and at maximum no more than two.
Your next instinct may be to create a second extra for Protein Choice, however note that the protein choices aren't the same for each item. Certain options come with a sauce and some don't and this is only offered for certain items. To summarize: the choice protein for the two items don't have to be the same so this adds additional layers of complexity.
A better way is to try and eliminate the need for the additional choices all together. List out the options like this:
Now the customer can choose two from this list and the protein choices are already included in the options!