In a medium bowl, cream the butter, brown sugar, and honey until light and fluffy. Add the vanilla and eggs one at a time until thoroughly incorporated. Add the AP flour, whole wheat flour, salt, cinnamon, and cardamom until just mixed.
Now you have two options for the cookies...the easier way or the prettier way. For the easier way, divide the dough in half and shape the dough into two 12-inch logs. Wrap in plastic wrap and refrigerate for at least two hours. Cut the chilled dough into 1/8-inch slices.
For the prettier way, divide the dough in half and chill for about 30 minutes. Roll the dough between two pieces of parchment paper until 1/8-inch thick. Use a 2-inch circle cookie cutter to cut out about 40 cookies.
Preheat oven to 350* F. Place the cookies 2 inches apart on ungreased cookie sheets. Bake for about 8-9 minutes, or until lightly golden brown. Let cool completely.
For the marshmallow buttercream...
While the cookies are baking, make the marshmallow buttercream. Cream the butter and marshmallow fluff together. Add the powdered sugar and vanilla. Whip for about 5 minutes, until light and airy.
Using a frosting bag with a small tip (or a plastic bag with the tip cut off), pipe a circle of marshmallow buttercream around the edges of half of the cookies. Spoon about 1 teaspoon of the salted caramel into the center of the marshmallow buttercream circles (the buttercream will keep the caramel from seeping out). Sandwich the other half of the unfrosted cookies on top of the frosted cookies, gently pressing to make little sandwiches! Place the cookies in the freezer for 15-20 minutes.
Meanwhile, melt the chocolate over medium-low heat (don't heat it too high or it will seize and be a chocolatey disaster). Dip half of each sandwich cookie into the melted chocolate. Sprinkle with flaky salt. Let the chocolate harden completely. Store in an airtight container in the fridge or in a cooler part of your kitchen (to keep the chocolate from melting). Serve cookies at room temperature. Enjoy!