Make the filling:
In a medium bowl, combine sweetened flaked coconut, condensed milk, confectioners’ sugar, vanilla bean paste and Coco Lopez. Mix until the confectioners’ sugar is completely dissolved and mixture is combined. Transfer filling to a container with a tight fitting lid and store in the refrigerator until ready to use.
Bake the cookies:
Preheat oven to 350 degrees Fahrenheit and place rack in the middle section of the oven. Line 2 baking sheets with parchment paper and set aside.
In a medium bowl combine the flour, salt, and baking powder. Set aside.
Place a small pot of water on the stove over low heat. Bring it to a simmer. Over the pot of simmering water, place a stainless steel bowl. Add the chocolate chips and butter, stirring occasionally until completely melted, smooth, and looks like pudding. Set aside to cool slightly.
Once the chocolate/butter mixture melts, combine eggs, sugars, and cocoa powder in a bowl of an electric mixer fitted with a whisk attachment. Mix on high until the mixture has doubled in volume and is very very thick, about 4-5 minutes.
Reduce the speed to medium and add the melted chocolate mixture to the eggs/sugar mixture and mix until combined. Add in the vanilla extract.
Reduce the speed to low and add flour mixture all at once. Mix until just combined. Fold in the milk chocolate chips.
With a cookie scoop (or a teaspoon), drop spoonfuls of dough onto prepared baking sheets.
Bake for 9-10 minutes, rotating the pan halfway through for even baking. Tops of cookies should appear crackled, but the interior will be soft and under-baked.
Assemble sandwich cookies:
Remove filling from the refrigerator. Place half the cookies flat side up. Add about 2 teaspoons or so of the coconut filling, sprinkle with slivered almonds, and top with another cookie. Press the cookie down so the filling reaches the edges. What are you waiting for? Go all in on that situation.
Makes about 25 sandwich cookies.