It’s time to move onto assembling the scones. Cut up your fridge-cold butter into .5in (1.3cm) cubes and place them in the freezer to chill. Then, add brown sugar and the zest from a second orange to a separate small bowl and repeat the same rubbing process as was used for the topping. Set the bowl aside while you prep the other ingredients.
Now, pour the cream into a medium bowl and, one at a time, whisk in the sour cream, egg, and (lastly) orange juice until each are fully incorporated. Set your wet ingredients aside.
Begin the dry ingredients by pulsing the flour, baking powder, baking soda, powdered milk, and salt in a food processor 3-4 times. Add in the orange-rubbed sugar and pulse again. Then, take the butter out of the freezer and add it to the food processor. Pulse the flour mix (another 3-4 times) until small pea-sized pieces of butter form.
Once that’s done, dump the flour/butter mixture into a large bowl and pour about half of the cream mixture into the bowl. Use a spatula or spoon to gently fold and stir the dry ingredients and cream mixture until it begins to incorporate into a rough dough. Add in the rest of the cream mixture. Once most of the stray flour is mixed in, abandon the spatula/spoon, pour the bowl’s contents onto your counter, and use your hands to finish mixing. Your warm hands, will begin to melt the butter if you work the dough for too long, so be gentle and quick. A bench scraper can be really handy here.
Now, shape the scone dough into a rough square and use the bench scraper or a knife to cut it into quarters. Shape each square into a circle roughly 10 in (25.4 cm) in diameter (it's okay if they are a little small) and flour the work surface and the dough if they start to stick. Top three of the dough circles with cranberry-orange jam. Spread it all of the way to the edges as evenly as you can. Then, stack the layers. Save the only piece without jam for the top layer. Once stacked, if needed, gently press and re-shape the stack until it is roughly 10 in (25.4 cm) in diameter and 1½in (3.8 cm) tall.
Using the sides of the ruler or a knife edge, slightly indent the top of the scone dough to give you guidelines for cutting. First, cut the dough round in half, then quarters, and then cut each quarter in half for 8 equal wedges.
Place each wedge onto a silicone or parchment lined baking sheet roughly 2in (5 cm) apart. Then, brush the top of the scones with some cream and sprinkle them with the sugar topping. Rest the dough in the fridge for at least 20 minutes.
While the dough chills, preheat your oven to 425°F (218°C). When ready, Bake the scones 5 minutes and then turn down the oven to 400°F (204°C) for another 12-15 minutes. Let the cranberry and orange scones cool for 5-10 minutes before eating and until fully cooled before storing.