Preheat nonstick griddle to 325 °F. Set oven on low and place plates on racks to warm.
If using milk and vinegar instead of buttermilk, then in measuring cup or small bowl combine milk and vinegar. Set aside for at least 5 minutes.
In small mixing bowl, uniformly combine dry ingredients.
In medium mixing bowl, whisk eggs. Add cooled melted butter and buttermilk or soured milk; whisk to combine. Pour in dry ingredients and mix with whisk just until lumps are gone.
Spray griddle with canola oil. Onto griddle, spoon batter about 2 inches apart, use about 1/3 cup for 4-inch pancakes. Cook until bubbles begin to appear on surface of batter. Use spatula to flip. Continue cooking until second side is brown. As pancakes cook, remove to warm plate in oven. Reapply oil spray between each batch of pancakes.