Add flour, salt and baking soda in a medium bowl; stir to combine.
Lightly beat egg in another medium bowl; add sugar, butter, and shortening and mix well with an electric mixer until smooth.
Add half & half, milk, buttermilk and vanilla; mix well.
Add the dry flour mixture to wet mixture while beating; mix until smooth.
Cover and chill overnight or at least 1-2 hours before usage.
Making waffles: Rub a light coating of vegetable oil on a waffle iron; preheat waffle iron. Leave batter out of the refrigerator to warm up a bit. Spoon 1/3 to 1/2 cup of batter into waffle iron; cook for 3-4 minutes or until waffles are light brown.