Chocolate cookies sandwiched with vanilla cream filling.
In a medium bowl, whisk together flour, cocoa powder, salt, baking powder, and baking soda. Set aside.
In the bowl of a stand mixer with a paddle attachment, beat together sugar and coconut oil on medium-high speed. Beat until mixture if fluffy. Reduce speed to low and add milk, egg, and vanilla paste.
With the mixer still on low, slowly add the prepared flour mixture. Mix until just combined. Divide dough into two equal parts. Flatten the two halves and wrap tightly in plastic wrap. Chill in the refrigerator for 30-45 minutes until dough is cold and firm.
Preheat oven to 350 degrees. Line baking sheets with parchment paper and set aside.
Work with one dough at at time. On a lightly floured work surface, roll dough to 1/4”. Using a 1 3/4” round cutter, punch out cookies. Transfer to prepared baking sheet. Space cookies about 1/2” apart from each other. Bake in preheat oven for 15 minutes, rotating sheets halfway through baking. Let cookies cool in the pan for a couple minutes before transferring to a wire rack to cool completely.
In the bowl of a stand mixer with a paddle attachment, cream together butter and coconut oil until homogenous.
Add powdered sugar and beat on medium speed until incorporated. Add vanilla paste and salt. Beat until smooth. Transfer to piping bag or use a small offset spatula to spread onto cooled chocolate cookies. Sandwich cookies together, one plain and one with filling.
*Finished cookies keep best in the fridge, but can last at room temperature for 2 days in a sealed container. Eat chilled or let come to room temperature.
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