Preheat oven to 350°F.

Whisk together flour, cocoa, baking soda, and salt in a bowl until combined.

Stir together buttermilk and vanilla in a small bowl.

Beat together butter, maple syrup, LorAnn Red Velvet Emulsion, and granulate sugar in a large bowl with an electric mixer at medium-high speed until pale and fluffy, about 3 minutes in a standing mixer or 5 minutes with a handheld, then add egg, beating until combined well.

Reduce speed to low and alternately mix in flour mixture and buttermilk in batches, beginning and ending with flour, scraping down side of bowl occasionally, and mixing until smooth.

For large whoopie pies like I made, spoon 1/3-cup mounds of batter about 2 inches apart onto 2 buttered large baking sheets. For small whoopie pies, use a tablespoon to scoop onto a butter baking dish.

Bake in upper and lower thirds of oven, switching position of sheets halfway through baking, until tops are puffed and cakes spring back when touched, 11 to 13 minutes.

Transfer with a metal spatula to a rack to cool completely.

Beat together butter, confectioners sugar, cream cheese, and vanilla extract in a bowl with electric mixer at medium speed until smooth, about 3 minutes.

Add the cream cheese mixture into a piping bag. Pipe the one side of the whoopie pie and make into sandwich.