So every Sunday, my wife decides what we're going to be eating for breakfast, snack, lunch, snack, dinner for the entire week. So right now, I've created a "Weekly Menu" Tab, which has the days of the week across the top, and breakfast, snack, lunch, snack, dinner down the side. Within the table, she can choose an item from a drop down list I've created which pull from a "Meal Options" tab.

So the next step is that I've begun entering in her recipes into a "Recipes" tab. What I'd like to happen is that once she has chosen, from the "Weekly Menu" tab, let's say Spaghetti for Lunch on Monday and Fajitas for Dinner on Monday. I'd like a new tab "Groceries Needed" tab, to begin to populate what groceries she will need to buy for Spaghetti and Fajitas.

The next challenge is combining similar ingredients (like if I need 5 tomatoes for the spaghetti, and 2 tomatoes for the fajitas), I'd like the "Groceries Needed" tab to output 7 tomatoes. Please help! :)