Whisk buttermilk, milk, eggs, and butter together in a large bowl.
Step 2
Combine flour, sugar, baking powder, baking soda, and salt in a bowl; stir into buttermilk mixture just until blended. Adjust batter thickness to your liking by adding more flour or buttermilk.
Step 3
Heat a large skillet over medium heat; coat with cooking spray. Drop batter by 1/4 cupfuls onto the skillet; cook until bubbles appear on the surface. Flip and cook until browned on the other side. Repeat with remaining batter.