Step 1:

In a medium-sized bowl, whisk together the flour, black cocoa powder, baking soda, and salt. In a separate large bowl, cream the granulated sugar, softened butter, and brown sugar using an electric mixer on medium-high speed until the mixture becomes smooth and fluffy. Add the egg and vanilla extract, mixing until fully combined. Gradually incorporate the dry ingredients into the wet mixture and blend until just combined. Cover the bowl and chill the dough in the refrigerator for a minimum of 30 minutes, or up to 2 days.

Step 2:

Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper. Using a medium cookie scoop (about 1 1/2 tablespoons), divide the dough into 24 portions, setting aside the remaining dough. Shape each portion into 1-inch balls and roll them in sanding sugar until fully coated. Place the dough balls on the prepared baking sheets, leaving 2 inches of space between each one. Flatten each ball into a 2-inch circle.

Step 3:

Take 1/4-teaspoon amounts of the reserved dough and roll them into smaller 1/2-inch balls, coating them in sanding sugar. Arrange two smaller dough balls on the top edges of the flattened circles to resemble ears. Gently pinch the tops to form triangular shapes.

Step 4:

Position two sliced almonds on each flattened circle, placing the narrow ends toward the center to simulate eyes.

Step 5:

Bake the cookies for 8 to 10 minutes, or until the edges are set. Allow the cookies to cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.

Step 6:

In a microwave-safe bowl, melt the chocolate chips in 10-second intervals, stirring between each heating session, until smooth. Pour the melted chocolate into a piping bag fitted with a small round tip, or into a zip-top bag with a small corner cut off. Pipe a dot of chocolate in the center of each almond and place a green M&M on top. Pipe another dot below the eyes and attach a brown M&M for the nose. Finally, pipe two whiskers on either side of the nose. Allow the chocolate to set before serving.

Step 7:

Make Ahead Tip: These cookies can be baked up to three days in advance. Store them in an airtight container at room temperature for optimal freshness.