The biscuit method is probably the simplest of all the Big Five mixing techniques. On first glance, it resembles Muffin Method in that the dry ingredients and the wet ingredients are mixed together separately before being combined. The key difference is that the fat, which is almost always a solid fat, is rubbed into the dry goods before the main mixing event begins.
What are the advantages to that? First, the “cutting in” of fat serves the function of coating and lubricating flour granules, which greatly reduces the ability of the gluten molecules they contain to bond to one another. Thus, the Biscuit Method makes baked goods tender. The other big thing the Biscuit Method does is make things flaky.
How’s that? Well remember the rubbing thing. Most of the time when you dive into a recipe that employs the Biscuit Method, you’ll come across instructions directing you to stop rubbing when the fat blobs are about the size of peas (or at the very least when the mixture starts to look “like corn meal”). The reason you do this is because flakiness is a direct result of odd-sized blobs of fat, which, when the dough is rolled out into a sheet, form semisolid layers. When the dough is baked these layers melt away, leaving long slender gaps in the structure. These gaps are what are responsible for the texture we know as “flaky”.
Like the Muffin Method, the Biscuit Method is characterized by minimal mixing. Once the dry ingredients and the wet ingredients finally come together, the less you work the dough the better. This is especially important with pie crust, where any gluten formation at all can lead to significant shrinkage and toughness. Which makes me think I should make a pie this week too. Whaddya say?