INGREDIENTS
4
Eggs, large
1/2 cup
Chocolate syrup
2 1/2 cups
All-purpose flour
1/4 tsp
Baking soda
1/2 cup
Brown sugar, firmly packed light
1
Confectioners' sugar
1 cup
Granulated sugar
1/4 tsp
Salt
2 tsp
Vanilla extract
1 cup
Butter, unsalted
1 cup
Buttermilk
8 ounces (by weight) Mexican chocolate, roughly chopped*