Preheat oven to 200 C / Gas 6, and grease two sandwich tins.
Melt the 3 tablespoons of butter and stir in the 2 tablespoons of caster sugar. Pour this mixture into one of the sandwich tins and carefully arrange the pineapples and glace cherries into the tin.
For the cake mix, cream together the butter and sugar in a large mixing bowl untill light and fluffy.
Sift together the flour, baking powder and mixed spice. Gradually add this to the butter and sugar mixture untill well combined. Then slowly add the beaten eggs untill the whole mixture becomes smooth.
Carefully spoon half the cake mixture on top of the pineapple lined tin and the other half of the cake mixture into the second tin. Place both tins into oven and bake for 20 minutes or until a skewers comes out clean when inserted into the cake.
Once cooked leave to cool on a wire rack. Once both cakes have cooled slowly tip them out and place them on a clean dry surface. Spread the jam onto the plain half of the cake and carefully place the second half (with the pineapple topping) on top. Serve.