Here's how you should do this -
1. Add a single product in E-junkie, with the price of 21.95 and enable VARIATIONS.
2. Add three variation names - FlavorChoice1, FlavorChoice2, FlavorChoice3
3. Add the flavor list as values for all 3 and also, in the values for choice2 and 3 add a value called "none" on the top.
Once you get the button code and paste it in your website, do this -
1. Add <input type='hidden' name='amount' value='0.00'/> within the button code.
2. You'll need JavaScript to handle the onChange event of all the dropdowns which will calculate the value of 'amount' based on the selected values in each of the dropdown. So just create an array of 46 (remember, we added none to the list) values=>prices and then use that to calculate the price.
That same function can be used to do the fancy image thing popcornpapa guys are doing.
Hope this helps!