Sponge Cake: 

1. Preheat the oven to 180C/350F fan.
2. Separate the egg whites and yolks carefully, placing the egg whites in the Ooni Halo Pro mixing bowl and the egg yolks in the large mixing bowl. Add 1 tablespoon of the caster sugar to the egg yolks. Set egg yolks aside. 
3. With only the egg whites in the Ooni Halo Pro mixing bowl and the geared whisk attached, set the mixer to 100% / 345 rpm and whisk the egg whites for 1 minute 30 seconds. 
4. With the speed still at 100% / 345 rpm, set the timer to 9 minutes and add the remaining caster sugar one tablespoon at a time every 10 seconds until all the sugar has been added. This should take about 3 minutes (adding the sugar early on will ensure that it fully dissolves into the egg whites).
5. Leaving the mixer running to continue whisking the egg whites, use your whisk to beat the egg yolks in the large mixing bowl until it’s pale in colour and doubled in volume, this should take about 2 minutes. Moving the whisk from side to side usually works best for this. 
6. Add the vanilla extract and 60ml of the milk into the egg yolks and whisk to combine, then sieve half the flour and the salt into the large mixing bowl and mix until just combined. Repeat with the remaining 60ml of milk and flour. 
7. Check the consistency of the egg whites once the mixer stops, the meringue should be thick and glossy and hold a firm peak (somewhere between soft and stiff peaks). If it’s still at a soft peak, whisk it for an additional minute at 100% / 345 rpm. 
8. Add a heaped tablespoon of meringue to the egg yolk batter and fold in with the silicone spatula until both mixtures are well combined. 
9. Add a third of the remaining meringue into the batter and fold through, scraping the bottom and sides of the bowl - aiming for about 10 folds per addition of meringue. The goal is to gently combine the two mixtures while retaining as much air in the batter as possible. 
10. Repeat another two times with the remaining meringue - you may have to add a few extra folds after the last addition to fully mix all the meringue into the batter. You should have a light fluffy cake batter at the end of this.
11. Pour the batter into the ungreased and unlined baking tin and smooth the top of the cake. Place the cake in the oven and then reduce the temperature to 160C/320F fan. Bake for 45-50 minutes or until a skewer comes out clean or with a few large crumbs only (do not open the oven door to check the cake until at least 40 minutes in to minimise the chance of the sponge collapsing). Turn the oven off and with the oven door slightly ajar, cool the cake in the oven for 5 minutes before removing it to cool completely. This additional step will help reduce the extent to which the cake deflates when it’s cooling.

Finishing the cake:

1. Once the cake is completely cool, leave it in the tin and poke all over with a skewer or fork. 
2. Mix the evaporated milk, condensed milk and whole milk together in the medium mixing bowl/ measuring jug until combined. 
3. Pour half of the milk mixture over the cake, making sure to pour it over the edges and let it sit for a few minutes to partially absorb before pouring the remaining milk mixture onto the cake. It’s normal for there to be a pool of liquid on the cake at this point. Cover and refrigerate overnight, but if you need it on the same day, for a minimum of 2 hours.
4. Shortly before serving, add the double cream and icing sugar into the Ooni Halo Pro mixing bowl and attach the splash guard. Whisk the cream at 50% / 195 rpm for 20 seconds, then increase the speed to 70% / 255 rpm for between 3-4 minutes until the cream reaches soft peaks (the cream will continue to firm up as you spread it on the cake so you want to underwhip it at this stage). Top the cake with the whipped cream and sprinkle with ground cinnamon to serve. 

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If you’d like to make the Tiramisu Tres Leches, see below for the amended milk mixture/topping ingredients and method (starting from ‘Finishing the cake’).

Milk Mixture:

90ml Whole Milk 

1½ tbsp Instant Coffee Powder

30ml coffee liquor (Baileys/Tia Maria/Kahlua)

1 can (410g) Evaporated Milk

1 can (397g) Condensed Milk

Whipped Cream Topping:

250g Mascapone

50g Icing Sugar

250g Double Cream or Heavy Cream

Cocoa Powder (to dust the cake)

Finishing the cake:

1. Once the cake is completely cool, leave it in the tin and poke all over with a skewer or fork.

2. Heat the whole milk (on the hob or microwave) until warm, then add the instant coffee powder and stir until it dissolves. Add the coffee liquor, evaporated milk and condensed milk and mix to combine. 

3. Pour half of the milk mixture over the cake, making sure to pour it over the edges and let it sit for a few minutes to partially absorb before pouring the remaining milk mixture onto the cake. It’s normal for there to be a pool of liquid on the cake at this point. Cover and refrigerate overnight, but if you need it on the same day, for a minimum of 2 hours.

4. Shortly before serving, add the mascarpone and icing sugar into the Ooni Halo Pro mixing bowl and attach the splash guard. Whisk the mascarpone at 50% / 195 rpm for 20 seconds, then increase the speed to 70% / 255 rpm and lift the splash guard cover to pour all the double cream/heavy cream into the mixer. Whisk for about 3 minutes, or until the mixture reaches soft peaks (the cream will continue to firm up as you spread it on the cake so you want to underwhip it at this stage). You will have to scrape the bowl down once to ensure the mascarpone is well incorporated into the cream. 

5. Cover the cake with the mascarpone cream and sprinkle with cocoa powder to serve.