A vintage baking secret my aunt shared with me years ago.

For a slightly different sweetness, you can swap half of the granulated sugar for light brown sugar, which adds a faint caramel note while still keeping the recipe at three ingredients. If you prefer a less-sweet cookie, reduce the sugar to 3/4 cup; the cookies will be a bit more delicate but still hold together. Use creamy peanut butter for the softest, most uniform texture—classic shelf-stable brands work best. Natural peanut butter that separates in the jar can make the dough oily or crumbly, but if that’s all you have, stir it very thoroughly and chill the dough for 20–30 minutes before baking to help it hold shape. For smaller households, bake half the dough and roll the rest into balls, freeze on a tray, then store in a freezer bag for up to 2 months; bake from frozen, adding 1–2 extra minutes. Always bake the cookies fully (no raw centers) and cool them on a clean surface or the foil-lined pan before stacking or storing. Because this recipe contains raw egg before baking, avoid tasting the dough and wash your hands and utensils after handling it. Store any leftover cookies in an airtight container at room temperature, away from direct heat or sunlight, and discard if they develop an off smell or texture.