Lemon bars are a sweet, tangy, and of course lemony dessert bar. Although lemon bars appear to be a 20th century invention, they are as popular as many ancient time tested favorites in some households, and many families have a recipe for lemon bars which is readily passed down to new generations. When well made, lemon bars will have a perfectly crumbly shortbread base, topped with a gooey lemon topping almost like custard, and a delicate dusting of powdered sugar.
Some people enjoy their lemon bars hot, fresh out of the oven. Others like to chill them, offering the bar cookies with a selection of other desserts at the end of a meal. Cooks with fancier aspirations may pipe pastry cream or whipped cream onto their lemon bars and top them with fresh fruit. This can elevate the already popular dessert to new levels of deliciousness, in the views of many consumers.
The origins of bar cookies appear to lie in the 1930s, when cooks started baking more cookies in large sheet pans. The inspiration was probably the brownie, another popular dessert which comes in the form of a cut square. Lemon bars appear to have hit the popular imagination in the 1960s, although variants may have been made by individual cooks before this period.
To make lemon bars, start by oiling an eight by eight inch (20 by 20 centimeter) pan. You can also line the pan with parchment paper or foil to make the cookies easier to handle if you so desire. Preheat your oven to 350 degrees Fahrenheit (177 degrees Celsius), and get started on the crust. Cream one half cup butter with one quarter cup powdered sugar and 1/8 teaspoon salt before slowing adding one cup of flour to form a loosely gathered dough. Press the dough into the pan and bake it for 20 minutes, until it browns, before pulling it out and adding the filling immediately. The heat of the crust will help to set the filling, ensuring that it cooks through.
For the filling, beat two eggs with one cup of sugar, and add the juice and zest of two lemons, along with two tablespoons of flour to help the filling thicken. Pour the filling onto the crust and bake the lemon bars until the filling sets. Sprinkle the dessert with powdered sugar, allow the bars to cool, and then slice them into single servings. In addition to lemon bars, you can also make lime, orange, or tangerine bars, if you're feeling adventurous; in all cases, use around 1/3 cup juice along with one tablespoon of zest. If you like your lemon bars more savory, cutting back on the sugar will not have a major impact on the recipe.