Prepare the Pan: Grease and flour a 10-cup dome-shaped cake pan and preheat the oven to 350°F (175°C).

Make Cake Batter: Cream together unsalted butter and granulated sugar until light and fluffy. Add eggs one at a time, then stir in vanilla. In another bowl, whisk together flour, baking powder, and salt. Gradually add to butter mixture alternating with milk.

Create the Swirl: Pour half the batter into the prepared pan, dollop raspberry preserves, and top with remaining batter. Use a knife to swirl the preserves without overmixing.

Bake: Bake for 45–55 minutes or until a toothpick comes out clean. Cool in the pan for 10 minutes before transferring to a cooling rack.

Coat with Coconut: Once cooled, brush with water or simple syrup and press shredded coconut all over the cake. Dust with powdered sugar if desired.