Make up the Blueberry Sauce:
In a small pot, combine the water, lemon juice, sugar, salt and cornstarch. Whisk until smooth. Add the fresh chopped blueberries and stir together. Bring to a boil over medium heat and cook for 4-5 minutes, stirring frequently. Remove from heat and allow to cool.
Making the Pancakes:
Lightly grease your griddle and preheat.
In a large bowl, mix up the flour, salt and baking soda. Add the egg, buttermilk, vanilla extract and butter. Mix until incorporated. Do NOT overmix. Batter will be thick, lumpy and kind of puffy. Gently stir in the 1/2 cup of chopped blueberries.
Spoon the batter onto the griddle. Quickly scoop some blueberry sauce right into the center of the pancake and use a knife to swirl it around a little.
Cook for about 1-2 minutes per side or until pancakes are golden.
Serve with more blueberry sauce on top and whole blueberries.