Preheat oven to 400° F. In a food processor, combine flour, granulated sugar, baking powder, salt, and butter and process until mixture resembles coarse meal, with a few pea-size pieces of butter remaining. Transfer to a bowl and refrigerate for 30 minutes - 1 hour. Stir in cream and buttermilk until just combined.
On a lightly floured surface, roll out dough to about 1-inch thickness. Use a large biscuit cutter to cut dough into 8 rounds (re-roll scraps once if necessary). Place, 1 1/2-inches apart, on a parchment-lined baking sheet. Brush shortcakes with cream and sprinkle with sanding sugar. Bake until golden brown and set, about 20 minutes. Transfer to a cooling rack to cool completely.
Meanwhile whip cream, confectioner's sugar and vanilla bean paste until soft peaks form.
Slice the shortcakes in half and spread each with Red Raspberry Jam. Top with raspberries and whipped cream. Serve immediately.