Bar cookies are baked in large sheets and portioned after baking.
- Prepare the dough or batter as directed.
- Spread the dough or batter evenly in the pan to ensure uniform baking. Some bar cookies, such as lemon bars, are made of layers of different components. Each component should be spread carefully and evenly; in some cases, it may be necessary to chill one layer before adding another layer.
- Bake as directed.
- If the bars are to be glazed or iced, allow the sheet to cool completely before adding the glaze or icing. To ensure clean, straight cuts, especially when working with a glazed or iced cookie, chill the full sheet before cutting it, and dip the knife in warm water and wipe it clean before each cut.
- Store in an airtight container. Bar cookies generally have a shorter shelf life than other cookies because the exposed sliced edges stale relatively quickly.