In a bowl, whisk together the flour, baking powder, sugar, orange zest, salt, and vanilla bean seeds until evenly combined. Cut in the butter with a pastry cutter until all pieces are small (pea-sized or less). Add cream and vanilla extract and fold in until incorporated. Use hands to gently knead everything together into a single ball of dough, adding a bit more cream if needed to bring dough together. Dough should not be wet or sticky.
Divide dough in half and shape each half into a round disc about 3/4" thick on prepared baking sheet. Freeze for 1 hour.
Preheat oven to 400ºF. Whisk together cream, vanilla sugar, and orange zest for glaze.
Cut each disc of dough, pizza-style, into 6 individual scones and spread apart on baking sheet. Brush tops with cream mixture and sprinkle with sparkling sugar.
Bake scones in preheated oven for 15-20 minutes, until a toothpick inserted into the center of one comes out clean. Transfer to a wire rack until ready to serve. Scones are best fresh, but leftovers can kept in an airtight container at room temperature.