Pre-heat oven to 180°C / 160°C fan and line a 23x23cm (9x9inch) baking tin with parchment paper.

Mix the melted butter, sugar, and coconut together in a small bowl. Pour mixture into the prepared baking tin and spread over the bottom to the edges of the pan.

Use a large round pastry cutter to quickly and easily trim the rind from each slice, then use a smaller round pastry cutter to stamp out the core from each slice. Cut all the pineapple slices in half.

Arrange the pineapple halves in any pattern you like in the pan on top of the sugar mixture, then set aside.

For the sponge, place all the ingredients in a large bowl then beat with an electric mixer just until combined.

Pour the cake batter into the baking tin on top of the pineapple, then smooth with a spatula.

Bake until a toothpick comes out clean, 60-70 minutes.

Leave to cool in the tin for about 15 minutes, then carefully turn out the warm cake onto a serving plate and carefully peel away the parchment paper.

Serve still warm or completely cool with a dollop of whipped cream or vanilla ice-cream.