First whisk together the flour, sugar, salt, and baking powder.
Then mix in the grated frozen butter until combined.
Mix in the cold milk until a dough starts to form.
Press the dough into a lined 8x8 baking pan then bake at 450F for 15-20 minutes.
While the shortcake is cooling, mix together cut strawberries and blueberries with sugar and set aside to get juicy, then assemble!