Nana made this for every spring gathering. Hard to believe it only takes 4 ingredients

If you like a stronger lemon flavor, you can increase the lemon juice slightly, up to 1 cup, but remember the filling will be a bit softer. For a more old-fashioned tang, use a mix of bottled lemon juice and a little fresh lemon zest stirred into the filling. If your store only has larger or smaller whipped topping containers, you can use anywhere from 6 to 12 ounces; more topping makes the pie lighter and fluffier, less makes it denser and richer. For a firmer pie that travels especially well to church or family gatherings, pop it into the freezer for 30 to 45 minutes before serving, but don’t freeze it solid—this is meant to be an icebox pie, not a hard ice cream pie. You can also swap the graham cracker crust for a vanilla wafer crust if that’s what you grew up with. Just keep the spirit of the recipe: four simple ingredients, mixed in one bowl, then into the icebox, just the way Nana did it.