Melt 4 tablespoons butter in the bottom of a large bowl; let cool.
Whisk in sugar, eggs, then 2 cups buttermilk.
Sprinkle surface of batter with salt, baking powder, and baking soda and mix thoroughly, scraping down bowl when you're done.
Add flour and stir just until combined; small to medium-sized lumps are fine.
If the batter seems too thick, add more buttermilk, a drizzle at a time, until you get the consistency you want.
Heat an electric griddle or large skillet over medium heat.
Spoon batter onto the griddle, add blueberries, flip when bubbles appear on top, cook until golden underneath.
Transfer pancakes to a serving platter or keep warm in the oven.
Serve with powdered sugar, butter, maple syrup, or as desired.