how to create shopping list from menu options?

hi guys,

trying to create an excel sheet where i can tick a meal option, and it will then tell me how many of the required ingredients i need to buy. fairly simple for the educated, and once i have the "base" formula i will hopefully be able to tinker it to my needs ;-)

heres a very basic screenshot of what i want to happen...excel screenshot.jpg

by inserting a "y" in the column next to "fajitas" i would then like the ingredients to all display "1", sure i can tinker if for example i need 2 onions!

Hope you can help

Cheers

Mark