Line two baking sheets with parchment paper.
In a small bowl, combine the buttermilk, vanilla and egg. Stir with a whisk to combine. Set aside.
½ cup buttermilk, 1 teaspoon vanilla, 1 egg
In a large bowl, combine the flour, sugar, baking soda, and salt. Stir with a whisk to combine.
2 ½ cups flour, ½ cup sugar, ¾ teaspoon baking soda, ½ teaspoon salt
Add the butter to the flour mixture. Using a pastry blender, cut in butter until it resembles coarse crumbs.
½ cup cold unsalted butter, cut into small cubes
Add the strawberries to the flour mixture and stir until strawberries are coated. Add the buttermilk mixture. Using a fork, gently stir ingredients together just until combined.
1 cup strawberries, chopped
Transfer dough to a very lightly floured surface. Use your hands pat the dough into a ball then lightly press into 8-inch disc. Slice into 8 wedges. Carefully transfer wedges to prepared baking sheets. Place baking sheets in the freezer for 15-20 minutes, or until the dough is fully chilled.
Preheat oven to 400°F.
Bake in 400°F oven for 16-18 minutes or until just starting to turn golden brown on the tops. Remove from the oven, let cool on baking sheet for 2 minutes before transferring to a cooling rack to cool completely.