01 - Preheat the oven to 400°F. Line a baking sheet with parchment paper.
02 - In a large bowl, whisk together the flour, sugar, baking powder, and salt until evenly distributed.
03 - Add the cold butter cubes to the dry mixture. Using a pastry cutter or your fingertips, work the butter into the flour until the mixture resembles coarse crumbs with some pea-sized pieces remaining.
04 - In a separate bowl, whisk together the heavy cream, sour cream, egg, and vanilla extract until smooth and combined.
05 - Pour the wet mixture into the dry ingredients. Stir gently with a spatula or wooden spoon just until the dry ingredients are moistened. Do not overmix.
06 - Gently fold in the diced strawberries using a light folding motion, being careful not to crush the fruit or overwork the dough.
07 - Turn the dough onto a lightly floured surface. With lightly floured hands, pat it into a 1-inch-thick round disk, approximately 7 inches in diameter.
08 - Use a sharp knife or bench scraper to cut the dough round into 8 equal wedges. Work quickly to keep the butter cold.
09 - Transfer the scones to the prepared baking sheet, leaving about 2 inches of space between each wedge for even baking.
10 - Brush the tops of each scone lightly with heavy cream using a pastry brush. Sprinkle coarse sugar evenly over the tops for a crunchy finish, if desired.
11 - Bake for 16 to 18 minutes, or until the tops are golden brown and a toothpick inserted into the center comes out clean.
12 - Let the scones cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely. Serve warm or at room temperature.