01 - Preheat the oven to 350°F. Line an 8-inch square baking pan with parchment paper, ensuring the sides are fully covered for easy removal.
02 - In a medium bowl, whisk together the all-purpose flour, baking powder, and salt until evenly distributed.
03 - In a separate large bowl, beat the softened butter and granulated sugar using an electric mixer on medium speed until the mixture becomes pale, light, and fluffy, approximately 3 to 4 minutes.
04 - Add the eggs one at a time, beating well after each addition. Mix in the vanilla extract until fully combined.
05 - Gradually add the dry ingredient mixture to the wet ingredients, alternating with the whole milk. Begin and end with the dry ingredients, mixing just until combined. Avoid overmixing to keep the sponge tender.
06 - Spread the batter evenly into the prepared baking pan. Bake for 22 to 25 minutes, or until a toothpick inserted into the center comes out clean. Allow the cake to cool completely in the pan.
07 - Once fully cooled, remove the cake from the pan and cut into 16 even squares. Place the squares in the freezer for 30 minutes to firm up, which makes the dipping process much easier.
08 - In a bowl, whisk together the sifted powdered sugar, raspberry jam or puree, and 2 to 3 tablespoons of whole milk until a smooth, pourable glaze forms. Add milk gradually to reach the desired consistency.
09 - Spread the desiccated coconut in a shallow dish. Dip each chilled cake square into the raspberry icing, allowing the excess to drip off, then roll gently in the coconut to coat all sides evenly. Place each coated square on a wire rack to set.