For my holiday baking this year, I decided to upgrade a few classic bar cookie recipes by giving them shortbread crusts. At first, I tried using my favorite shortbread recipe, which makes a great cookie, but it was too delicate and crumbly to work as crust. Clearly, I was going to have to tweak the recipe. My goal was to develop a crust that had the buttery tenderness of shortbread but was crisp and strong enough to be the foundation of a bar cookie.

From cookie to crust: a new mixing method for a new kind of shortbread

Most shortbread recipes are variations on a classic ratio of three ingredients: 1 cup flour, 1/2 cup butter, 1/4 cup sugar. Over the years, I’ve tweaked the ingredients, trying out different kinds of flours and sugars, but I never dared tinker with the mixing method. Always, I’ve begun with soft butter and stuck to the classic creaming method, which yields a tender, slightly sandy shortbread.

Melted butter is the key. In a moment of inspiration, I decided to try stirring melted butter into the dry ingredients instead of beating them together with soft butter. Not only was this method easy, but it delivered the crisp crust I wanted.

Refrigerate the dough before baking. Chilling the dough briefly after pressing it into the pan ensures the perfect texture. Cold dough doesn’t puff up and shrink as much as room temperature dough during baking, so the crust is perfectly crispy-crunchy.

And now for the fun: scrumptious toppings

For the toppings, I’ve chosen classic flavors that everyone loves, because I intend to give these bars as gifts. Two of the bar cookies have nuts and chocolate, always a crowd-pleasing combination. One is topped with crunchy pecans, chewy caramel, and chocolate; the other is covered with a creamy peanut- butter spread and bittersweet chocolate ganache. There’s also a lemon bar and a cranberry bar. With its sweet-tart flavor and creamy, delicate texture, my lemon topping is similar to lemon curd but easier to make. The cranberry streusel bars (my favorite) have a tangy cranberry filling that keeps the ultra-rich crust and streusel in check.