Preheat the oven to 350ºF. Grease and flour a 9x9 metal baking pan Chicago Metallic on Amazon)
Warm the milk with the butter to melt them together in the microwave or a small saucepan. Add the vanilla and set this aside to cool.
In the bowl of an electric mixer fitted with the whisk attachment (I have also done this successfully with the paddle attachment!), beat the eggs and sugar until they are light and fluffy and creamy coloured (this takes a good 5 minutes of beating), then add in the salt.
Sift the flour and baking powder into a separate bowl.
Add the flour mixture, alternating with the warm milk mixture, beginning and ending with the flour.
Transfer the cake batter to the prepared pan and bake for about 35 minutes until the sides are golden brown and pull away from the pan, and a skewer inserted into the center of the cake comes out clean.
Unmold after 5 minutes onto a wire rack to cool completely.
Prepare the quick jam
Mash together the raspberries and water in a microwave safe bowl, and heat them in the microwave for 1 to 2 minutes to extract the juices. Purée the raspberries with a hand blender and strain the juice into a medium saucepan.
Add the sugar and heat to cook and thicken the jam. I cooked the jam to 215ºF.
Transfer to a bowl and let cool.
Assembly
Cut & trim the cake into 25 cubes (~1.5"x1.5").
Dip the bottom & top of each cube in the quick jam, smoothing off any excess, and then in the coconut.