I just learned that there will be leaf lard available at the UD farmers’ market this weekend. Hallelujah! It’s the softest, sweetest, bestest lard a pig gives, straight from the fat surrounding the kidneys. But this stuff ain’t from just any pigs – it’s from Berkshire hogs raised by Wooly Pigs rancher Heath Putnam, the guy whose super-marbled Mangalitsa pork will reportedly be available next summer. This is phat pig fat.Of course, most people want Heath’s Berkshire chops and jowl bacon for their Christmas parties, but I’ll be there to buy the leaf lard, because I want to make a pie.Here’s a bit of quick, oversimplified baking science: When you make a pie crust, you layer little pieces of butter, or shortening, or what have you, between layers of flour (whose gluten, when mixed with water, becomes activated . . .but that’s another topic entirely). When the butter melts, it produces steam, which pushes the floury stuff apart, resulting in the little air pockets we come to know on our tongues as flaky pie crust.But see, leaf lard is made up of bigger fat crystals than butter. In pie making, this translates to bigger air pockets, and thus a much flakier crust. Some argue that butter has a better flavor, so many recipes call for a combination of leaf lard and butter. I’ve always wanted to try it. Because who wouldn’t love a pig-and-apple pie?There’s one little catch: When you buy leaf lard, you can’t just chop it up and throw it in the mixer like butter. You have to render it yourself before using it.But what the hay? It’s baking season, when we’re all game for something new. Why not try a pig fat pie?Wooly Pigs at the University District Farmers’ Market, Saturday 9 a.m. – 2 p.m.