In a medium bowl, whisk together the all-purpose flour, baking powder, baking soda, and salt.
1¾ cups all-purpose flour, 1 teaspoon baking powder, ½ teaspoon baking soda, ½ teaspoon salt
In a separate large bowl using an electric mixer, or use a stand mixer, beat the butter and granulated sugar until light, fluffy, and very pale in color; at least 2-3 minutes.
5 tablespoons butter, 3/4 cup granulated sugar
Add the eggs, one at a time, mixing well after each addition. Mix in the vanilla extract until combined.
2 large eggs, 1 teaspoon pure vanilla extract
Add the sour cream and milk, and mix until smooth and evenly combined.
1/3 cup full-fat sour cream, 2 tablespoons whole milk
Add the bowl of dry ingredients into the large bowl of wet ingredients and gently fold, using a spatula or wooden spoon, just until combined and no flour streaks remain in the batter. Set the batter aside and let it rest for 5-10 minutes so it can thicken slightly.
While the batter is resting, add the chopped strawberries into a bowl with the all-purpose flour and stir it together until all the strawberries are coated. When the batter is done resting, gently fold in the flour coated diced strawberries and just barely mix until combined.
1¼ cups fresh strawberries, 1 tablespoon all-purpose flour