How to Make It
Preheat oven to 325° F. Whisk together buttermilk, sugar, butter, flour, egg yolks, vanilla extract, and salt.
Pour the mixture into the piecrust and bake until the center is set but still slightly wobbly, 40 to 50 minutes. Let cool, then chill until firm, 4 to 5 hours.
Top with raspberry jam and toasted sliced almonds before serving.