Preheat the oven to 450 degrees
Use a paper towel to remove any excess moisture from the blueberries. Toss the blueberries with 2 teaspoons of flour.
Combine the rest of the flour, sugar, baking powder, and salt in a large bowl.
Cut in the butter with a pastry cutter. There may still be pea size chunks visible in the dough.
Stir in the buttermilk until barely combined.
On a well floured surface, roll out the dough to a rectangle shape about ½ inch thick and lightly press your blueberries evenly throughout the dough.
Mentally divide the rectangle into 3 equal pieces. Fold the right third over the center. Then fold the left third over the center. (This is like folding a letter.) Now you have a stack 3 slabs high. (If you find it easier to cut 3 equal pieces, that’s fine. Just stack up the 3 equal pieces.) Then carefully roll out the dough to ½ inch thick again. (This is going to help the layers puff up.)
Cut out five biscuits with a 3 inch cutter. Try to handle the dough as little as possible, so that the butter stays cold but you will need to reshape and roll out the dough again to cut out 5 more biscuits.
Put the biscuits about an inch apart on an ungreased baking sheet, then push a few blueberries into each biscuit.
Bake for about 7 minutes, then take the biscuits out and generously brush with melted butter. Return them to the oven and bake for 3 more minutes or until golden.
While the biscuits are baking, make the glaze. Stir together the powdered sugar, milk, and lemon juice until smooth.
When you remove the biscuits from the oven, allow them to cool slightly and then drizzle with the glaze.
These are best served warm!