In the bowl of an electric mixer, cream together butter and shortening. Add sugars, baking soda, and salt, and beat together until well combined. Beat in eggs and vanilla. Add flour, cocoa and seasoning gradually, until mixture is just combined.
Drop the dough by rounded tablespoons onto a Silpat or parchment lined baking sheet, about two inches apart.
Using a piping bag fitted with a round tip (I used a #7), insert the tip into the side of each mound of dough and squeeze marshmallow cream inside.
Bake for 8 to 9 minutes, or until edges are firm. Allow to cool on baking sheet for 2 minutes, then move to a cooling rack.
Drizzle with caramel syrup, if desired
Notes
adapted from Better Homes and Gardens Fall Baking, 2012
Recipe by Kitchen Meets Girl at https://kitchenmeetsgirl.com/chocolate-caramel-marshmallow-cookies-and-kernel-seasons/