Heat oven to 375 degrees F and line a baking sheet with a silicone mat, or parchment paper. Set aside.
In a large bowl, combine flour, bran, baking powder, salt and brown sugar. Mix well.
In the bowl of your food processor, add flour mixture and butter. Pulse a few times until the butter is incorporated but still has pea sized pieces. Alternately, you can use your hands or a pastry blender to work the butter in.
Return the mixture to the large bowl and add sour cream (or yogurt) and heavy cream. Stir until the mixture just comes together.
Knead once or twice, but not too much. You don't want to overwork them.
Roll dough out on to a well-floured surface. Use a rolling pin and roll out the dough to approx 1/2-inch thickness. Cut into 10 (2 1/2-inch) rounds.
Carefully transfer the scones to the prepared sheet pan. Use your thumb to make an impression in the center of each round. Scoop 1/2-1 teaspoon jam into the center of each round.
Now, go back to the scraps of dough and gently re-roll the dough to get another 10 rounds.
Brush the edges of each jelly-filled rounds with egg wash and carefully place a new blank round (without jelly) on top. Press together gently at the edges to seal in the jam.
When you've finished assembling each scone, brush the tops of them with egg wash and sprinkle generously with 1/4 teaspoon or more of raw sugar.
Bake in the oven for 16-19 minutes. Remove from the oven and let the scones cool on the tray for 5 minutes before transferring them to cooling racks.