The Pantry Mangia! maintains is handy for finding recipes you can Cook Without Shopping and for winnowing down a Shopping List. The Shopping List Window, which shows you a list of ingredients grouped into recipes, automatically checks its ingredients against the Pantry; it marks those ingredients currently found in the Pantry with an asterisk (*). You can select all of the found ingredients via the Shopping List Menu and delete them from the list en masse if you know that your Pantry is current. 

Even if you don’t have total confidence in the accuracy of your Pantry, you can use the Shopping List Window to help you maintain your Pantry painlessly. There are two buttons at the bottom right of the window which you can use to directly add or remove any selected ingredients to or from the Pantry. Here’s the general procedure:

First, scan down the marked ingredients. If you're like most people, you'll be reminded of several things you no longer have. As you scan through the list, simply Shift-click to select the offending items. When you get to the end of the list, you can click on the Remove From Pantry button (it shows a pantry with an ingredient missing) at the bottom of the window. The Pantry will change, and all of the selected ingredients should then have their asterisks removed. (It's possible that some ingredient is marked because it belongs to an ingredient Category listed in the Pangry. In that case, Mangia! will ask if you want to remove the entire Category from the Pantry.)

Now, scan through the remaining ingredients. You will probably notice some items that you know you do have on hand. Simply select those (Shift-click accumulates a selection) and click on the Add to Pantry button (it shows a hand adding an item to a pantry) in the window. All of those ingredients will now be starred, to indicate that yes indeed, Mangia!  now believes that you have those on hand.