To Make the Pineapple Jam
Grate the pineapple into a thick and coarse pulp.
Place the pineapple pulp and sugar into a large saucepan. Bring to the boil, then lower the heat to medium.
Cook the jam until it thickens to a spreadable consistency, stirring occasionally. Set aside to cool.
To Make the Roll Cake
Preheat oven to 180°C. Grease and line a 25cm square cake tin.
Beat the eggs and sugar with an electric mixer until fluffy.
Add the vanilla extract and sift in the flour. Fold through gently with a rubber spatula.
Pour the batter into the cake tin. Bake for 12 mins.
Remove the cake from mould immediately, then spread the pineapple jam on top. Carefully roll the cake and allow to cool seam side down.
Allow to cool completely before slicing to serve.