Preheat your oven to 350℉. Lightly grease 15 muffin cups or line them with paper liners.
Whisk together the gluten-free flour blend with the baking powder and salt in a small bowl. Set this aside for later.
In a large bowl, combine the softened butter and granulated sugar. Beat on medium-low speed until the mixture is thick.
With the beater still running, add the eggs one at a time. Beat until the mixture is fully combined.
Add the dry ingredients and mix on low speed until the batter is thick. Stop the mixer and add the milk and vanilla extract. Mix until a thick, smooth batter forms.
Gently fold in the blueberries with a rubber spatula. If you are using frozen or cold blueberries, the batter will get very thick, which is totally normal.
Spoon the batter into the prepared muffin pans. Fill each cavity about ⅔ full. Top each with about 1 teaspoon of granulated sugar if you like a little crunch.
Bake until a cake tester inserted into the center comes out clean, about 25 minutes.
Allow the shortcakes to cool in the pan for five minutes. Transfer them to a wire rack to cool completely.
While the shortcakes bake, toss the sliced strawberries with 2 tablespoons of sugar in a bowl. Let them sit at room temperature to macerate.
In a chilled bowl, whisk the heavy cream, powdered sugar, and vanilla until soft peaks form. Keep this in the fridge until you are ready to serve.
To assemble, slice a cooled shortcake in half horizontally. Place the bottom half on a plate and spoon a generous amount of macerated strawberries and juice over it.
Add a dollop of whipped cream, place the top half of the shortcake on, and finish with one more spoonful of berries and cream.