Heat oven to 450°F. Coat a 9-inch straight-sided aluminum cake pan with 1 teaspoon of lard.
Whisk the all-purpose flour, whole wheat pastry flour, baking powder, and salt together in a large bowl. Quickly cut the lard until the mixture resembles coarse crumbs. Stir in the buttermilk using a large, wide spatula until the dough just comes together. The dough will be very loose and shaggy.
Dump the dough onto a lightly floured counter, fold it over onto itself 6 to 8 times and pat to 1/2-inch thickness. Dip a 2-inch biscuit cutter into flour and cut biscuits. Press the cutter straight down and do not twist. Place the biscuits in the prepared pan so that they are just touching each other and the side of the pan. Fold together the remaining dough and repeat cutting. Press down lightly in the center of each biscuit with a fingertip.
Set the pan on the middle rack of the oven and then boost the oven to 500°F. Bake until golden brown, 12 to 14 minutes. Cool for 3 minutes in the pan before devouring.