Step 1

Mix milk and vinegar in a medium bowl and allow to sour for 5 minutes.

Step 2

Sift together flour, sugar, baking powder, salt and baking soda in large mixing bowl.

Step 3

Whisk egg and butter into soured milk.

Step 4

Fold flour mixture into soured milk and whisk until clumps are gone. Do not overmix.

Step 5

Allow batter to rest in a chilled area for at least 4 hours, preferably overnight.

Step 6

Heat large skillet over medium heat and coat with cooking spray.

Step 7

Pour 1/4 cup of batter onto the skillet and cook until surface is bubbly.

Step 8

Flip with spatula and cook until browned on other side.

Step 9

Serve with maple syrup (if using) and butter.