Baked on September 8, 2018
I have a confession. This week I became a lemon torturer. Making lemon meringue pie this weekend, I chopped, squeezed and zested five lemons. Though their life came to a brutal end, I'd like to believe they knew their life had purpose. What better purpose than pie?
I'd say baking gives me purpose... or at least a "zest" for life! So let's "squeeze" the day and start baking!
Lemon Meringue Pie is assembled in three steps. First you bake the pie shell, then make the lemon filling to fill the pie shell, and lastly top off the pie with meringue. To make the dough for the crust, I first combined the flour and salt until well mixed. Next, I added chunks of butter to the flour mixture and mixed until there were still ~2cm sized chunks of butter in the course mixture. These remaining small chunks of butter will allow for a flakier consistency of the crust. While still mixing, I added all of the water in one pour and continued mixing briefly as the dough came together. Turning the dough out onto a lightly flowered surface, I formed a ball, tightly wrapped it in plastic wrap and refrigerated the dough for one hour.
Next, I rolled the dough out onto a lightly floured surface. In reading about pie doughs for this bake, I learned that bread flour actually works best for lightly flouring a surface. Due the lower starch content, it is less likely to clump up and introduce large spots of flour into your dough. The dough was already pretty malleable, so it was easy to roll out to about 1/8 inch thickness.
I next folded the rolled out dough over my rolling pin to gingerly lay it onto the pie dish, gently easing the dough up the the sides of the dish. I then trimmed any excess dough from the edges and used two index fingers to crimp the dough at the rim.
Next I blind baked the pie shell so that it is fully cooked and crispy before any lemon filling is added. Blind baking is the method of baking the shell without filling in the presence of heavy baking beads or dried beans. To do this, I lined the prepared pie shell with parchment paper and then filled it with the heavy beans. I then baked the shell with the beans to weigh down the dough so it maintained its shape in the dish. The tricky part of blind baking is knowing when the crust is done. When I pulled the dish out of the oven and removed the beans, I discovered that the center of the dough was not yet finished and I put it back in the oven for about ten minutes without the beans.
Now that the the pie crust was done, it was on to the lemon filling! I first mixed lemon juice, lemon zest, granulated sugar and water in a saucepan and brought it to a boil. In the meantime, I mixed sugar and cornstarch into egg yolks and water in a separate bowl. Once the lemon juice mixture was boiling, I poured about a third into the egg yolk mixture to temper it, and then added the egg yolk / lemon mixture back into the lemon juice mixture in the saucepan. I brought this mixture to a boil while stirring until the mixture thickened. I then stirred in a small amount of butter. This lemon mixture was then immediately poured into the cooled pie shell to set.
So why does cornstarch, when heated in a mixture, cause a sauce to gel? The strands of starch actual begin to absorb water in the mixture. When heated, the water molecules are moving more quickly, causing disruption of the starch molecules, allowing them to absorb even more water. As the starch begins to restrict more water, it forms a gel. Once cooling off the stove, the sauce tends to gel further as the starch structures stabilize into a form that is more permanently restricting the water.
Now that we've got our lemon filling, what's lemon meringue pie without the meringue on top? In the final step, I whipped the eggs and sugar until glossy and forming stiff peaks in the bowl. Then loading a piping bag fitted with a star tip, I piped rosettes onto the surface of the cooled lemon filling. The whole pie then went into the oven for a few minutes, allowing the edges of the meringue to develop a golden brown look.
And we're done! The pie turned out super well. Usually my husband takes these bakes in to work with him... but honestly... it didn’t make it to work with him this time!!
Although this pie turned out super yummy, there were a few things I learned:
There are a few methods of blind baking. Some people will only bake the shell in the presence of the beans or weights for the first 10 minutes and then remove the weights for the remainder of the baking. This may have sped up my baking time and allowed the rim of my crust to stay a bit more tender rather than crispy from spending too long in the oven.
My meringue ended up shrinking away from the edges and left moisture on top of the lemon filling. After reading a bit online about this, I learned the phenomenon is called "weeping." As I learned, weeping of the meringue can happen for a handful of reasons. However, in my case it was definitely due to spending too much time in the oven at the last step. The recipe said it would only need ~3 minutes in the oven, but since the pie wasn't turning a pretty golden brown, I left it in for much longer. Other suggestions I read include 1) using super fine sugar so that it dissolves better in the egg while whipping, 2) preparing the meringue ahead of time so that you can apply it while the lemon filling is still hot and can help 'bake' the meringue, or 3) only baking the pie on low humidity days.