Instructions:

For the cake:

Preheat oven to 350 Deg F. Line an 18x13 rimmed baking sheet with parchment paper. You might have to use two pieces of parchment

In a large bowl whisk together the egg yolks, 30 g of sugar, oil, pineapple juice and vanilla. Sift the flour and salt over the top and whisk together until no lumps remain.

In a stand mixer or another large bowl, whisk the egg whites until foamy. Add the cream of tartar and whisk another minute. Keep whisking and slowly add in the sugar and turn mixer to medium high and whisk until soft peaks form. When you lift the whisk out of the bowl the whipped egg white peaks will slowly fold back over.

Fold the egg whites into the yolk mixture one third of the whites at a time. Being careful not to deflate the whites. Once it is all folded in, pour into the prepared pan and smooth out to all edges of the pan as evenly as you can. Tap the pan on your counter a few times to release air bubbles.

Bake for 8-10 minutes or until the top is starting to brown and looks dry. No longer than 12 minutes.

Remove from the oven and cool. Cut in half lengthwise so you have two pieces roughly 9x13. You can wrap these and keep chilled until ready to use.

To make the ice cream:

If using pineapple chunks, blend the pineapple and its juice until its the same consistency as crushed, not pureed smooth. Transfer the blended pineapple and juice to a saucepan and heat over medium high, stirring until the pineapple juice has evaporated and the pineapple mixture has thickened. Let cool.

In a large bowl whisk together the coconut milk, whipping cream and condensed milk. Mix 50 ml of the pineapple juice with the Pina colada mix and the rum. Whisk this into the milk mixture. Whisk in the remaining 200 ml pineapple juice and lime juice then add in the cooked pineapple.

Transfer to two large deli containers and chill for an hour. You will be churning the ice cream when ready to assemble the ice cream sandwiches.

Ready to assemble:

Line a 9x13 rimmed baking sheet with 9 inches of parchment paper hanging over the long sides. Place one half of the cake on the pan.

Churn the ice cream then spread it over the top of the cake half in the pan. There will be some leftover.

Top with the other half of the cake, fold the parchment paper over the top then freeze until the ice cream bars are set.

When frozen, remove the slab of ice cream sandwich, trim the edges then cut into 10 bars. You can refreeze these if they get melty while cutting.

Store either individually wrapped in wax paper or parchment in a freezer safe bag or freezer safe container.