Melt butter in a large bowl. Add egg and blend completely. Mix in sour cream until smooth. Set aside.

Combine all dry ingredients in a large bowl and mix thoroughly.

Do not mix sour cream mixture and dry ingredients until griddle is hot (375-400° F) and you are nearly ready to serve.

Add sour cream mixture to dry ingredients; add 1/4 to 1/2 cup of milk, then stir as little as possible. Do no overmix.

Immediately cook on hot griddle. When turned, pancakes will puff up. Brown on both sides but don't overcook. These pancakes must be served immediately. They cannot be prepared in advance.