Preheat your oven to 400 degrees F and line two baking sheets with parchment paper.
In a large bowl, add the 2 ¾ cups all-purpose flour, ⅓ cup sugar, ¼ teaspoon fine grain salt, and 1 tablespoon baking powder. Mix together using a whisk or a spoon.
Add the 8 tablespoons cold salted butter cut into cubes. Use your hands to kind of "smush" the butter pieces into the flour, until texture is crumbly and butter pieces are no bigger than peas (it's OK if some pieces of butter are different sizes). Alternatively, you can use a pastry cutter to incorporate the cold cubed butter into the flour.
In a small bowl, mix the 1 ½ cups fresh blueberries with 2 tablespoons of flour until all of them are well coated (try to make sure the blueberries are as dry as possible after washing them). Add the coated blueberries to the flour and butter mixture, including any extra flour lingering at the bottom of the bowl.
In a small bowl or glass measuring cup, beat the 2 large eggs with the ½ cup whole milk or half-and-half, and the zest of one lemon, if using. Make a well in the center of the flour and blueberry mixer in the large bowl. Pour the egg and milk mixture into the well, and mix together gently until everything is just incorporated and there is no dry flour left, taking care not to over-mix and trying not to smush the blueberries in the process (though some inevitably will get smushed eventually!). If dough seems too dry, like it can't be shaped together at all, you can add a little more milk or half-and-half as needed.
Turn dough out onto very well-floured surface and flatten carefully into a rectangle shape, using well-floured hands or a roller, until about ½ - ¾ - inch thick.
Cut the dough into squares about two inches wide. Then, cut each square on the diagonal to cut each of those squares into two triangles (tip: a rolling pizza cutter makes easy work of this, cutting first into strips in one direction, then squares in the other direction, then on the diagonal to make triangles). For any pieces that are very misshapen or edges that didn't get cut into shapes, you can reform to cut into triangles.
Place scones on a the parchment-covered baking sheets at least 1 inch apart.
Brush the tops of each scone with milk or half-and-half. (Optional: at this point, you can also sprinkle with turbinado sugar or white sugar for a crunchy top.)
Bake at 400 degrees F for approximately 18 minutes, or until golden brown. If baking both trays at once, rotate racks halfway through. Allow to cool for at least 10 minutes before serving.
Notes
Freezer directions: These mini scones can be frozen in an airtight container or plastic bag for up to 6 months. To thaw, microwave for 20-30 seconds.
Unsalted butter may be used; in this case, use ¾ teaspoon salt.
You can make other shapes besides triangles if you like. Make 1" squares instead of triangles. Another option is to use a simple cookie cutter, like a heart, or a circular biscuit cutter, to make circle shapes. I prefer triangles because you don't have any "extra" dough that you have to either rework, which affects the texture, or discard.
Using frozen blueberries is fine, but keep in mind because they are wetter/juicier, the scones may have an overall purple color. I recommend coating them in flour as directed while they are frozen, then proceeding with the recipe.
You can also make this recipe into larger scones. Just cut the shapes larger and cook for about 22-25 minutes, spaced 2-3 inches apart.
The amount of scones this recipe yields will depend on how big they are cut. I got about 40 out of one batch.
If you use buttermilk instead of milk or half-and-half, swap out the baking powder for baking soda.