Preheat oven to 425º F. Cover a baking sheet with parchment paper, or spray with cooking spray.
In a mixing bowl, combine flour, salt, baking powder and baking soda with butter, using your hands to break up the butter and lightly combine. Will be chunky.
Make a well in the middle of the flour mixture and pour in applesauce, buttermilk, Truvia, and beaten egg. Lightly mix together. Before mixture is completely combined, add in blueberries and lightly fold. Dough should be fairly stiff and not sticky. If it's sticky, add a bit more flour.
Split dough in half and make into two round 6" discs. Place on prepared pan and flatten a bit with your fingertips.
Drizzle tops with lemon juice, then sprinkle with the other 1 Tbsp. Truvia.
Cut into 8 slices each circle, for a total of 16 OR 4 slices each circle, for a total of 8 scones. Bake for 18-20 mins or until tops are golden brown.
Let cool a bit and then mix together powdered sugar and milk and drizzle over the tops of each scone. Serve and enjoy!