1. Prevent too much leakage
This batter WILL leak through the bottom just a bit. So make sure to wrap the outside with foil. The foil needs to come up to the sides & the tin. Press it against the edge & sides to secure.
2. Greasing & lining your baking tin
We can only speak for the paper baking tins on this one, but you don't need to line the bottom with baking paper. That's because once the cake is baked, we found the custard did seep underneath the baking paper & second, the bottom liner doesn't stick to the custard layer anyway.
We do recommend lining the inner sides, with >2cm of overhang as a safety precaution because the batter fills up the paper tin right to the top.
3. Removing the cake
Be gentle, as this cake is delicate. If you refrigerate the cake for 2+ hrs (or overnight) until it is completely chilled, handling it shouldn't be a problem (like how we did in the video.)
Try at your own risk, but we don't recommend removing the bottom liner AT ALL if your cake does still feel a tad warm. The soft custard middle layer would still not have set at that stage & so once you cut into it, the custard layer would just ooze out.
(BUT can I just say, I personally prefer eating the magic cake when it's just a tad warm because the middle layer is super soft & gooey. It did taste a little 'eggie' to me, but that did go away after a few hours. Emily x.)