Preheat the oven to 425°F (220°C) and place a rack in the center. Line a baking sheet with parchment paper and set aside.
Prepare the dry ingredients: In a large bowl, combine the flour, sugar, baking powder, and salt using a fork or whisk. Add the cold cubed butter pieces. Using a pastry blender or your fingers, cut in the butter until the pieces are no larger than a pea. There should be some chunks of butter still visible in the flour mixture.
Prepare the wet ingredients: In a medium bowl or a large liquid measuring cup, combine the sour cream, ½ cup heavy cream or milk (reserve the 1 TBSP), and the blood orange zest. Create a well in the center of the dry ingredients, then pour in the wet ingredients.
Using a fork, stir until everything just starts to come together. If the dough looks too dry, add the additional TBSP of cream. Add the raspberry and blood orange pieces. Gently stir the dough until everything is just combined. Do not overwork the dough (it’s ok if there are some dry spots still visible).
Turn the dough onto a clean, lightly floured counter or board. Using a bench scraper and your hands, gently fold the dough over onto itself a few times. The dough should be slightly sticky, but not too wet. Pat the dough into an 8-inch-diameter circle, about 1 ¼ inches thick.
Using a large sharp knife, cut the dough into 8 wedges. Transfer the wedges to the parchment-lined baking sheet, leaving about 2 inches of space between each scone. Chill the unbaked scones for 15-20 minutes in the freezer. Bake for 18 to 20 minutes or until golden brown on top. Immediately move the scones to a cooling rack to cool down before topping with the glaze.
Make the glaze: Combine the glaze ingredients until smooth. If the glaze is too thick, add a little more blood orange juice. If the glaze is too thin, add powdered sugar one TBSP at a time, until desired thickness.
Once the scones are cool, use a spoon to drizzle the glaze on top. Allow the glaze to set for 5-10 minutes before serving (if you can wait that long!).