In a medium bowl, sift together the flour, sugar, baking soda, and salt.
In another bowl, whisk together the eggs, milk, starter, melted butter, and vanilla until well blended. Add the dry ingredients, and stir just until combined, adding more milk, 1 teaspoon at a time, if necessary to bring the batter to the thickness of heavy cream. Be careful not to overmix,† and don't worry if batter is slightly lumpy.
Lightly grease a large, heavy griddle or skillet with vegetable oil and heat over medium-high heat. Pour about 1/4 cup of batter onto the griddle for each pancake, allowing space for spreading. As the topsides start to bubble, about 1 minute, sprinkle blueberries into each pancake. When the undersides of the pancakes are golden and the blueberries are set, flip with a wide spatula. Cook until golden brown, 1 to 1/2 minutes. Cook over break. Serve immediately with fresh butter and syrup.
Yield: 16 (4-inch) pancakes