Cheddar cheese cotton cake

I made this cheddar cheese cotton cake yesterday, I get the recipe from DG , Tested and Tasted
Thank you DG, this cake so yummy, better than Japanese cheese cake I made before, I like the taste of cheddar cheese in it, better than cream cheese. I didn't use double boiler method like the recipe said, instead I used microwave to make it easier.
I double the recipe than the original one.

Ingredients:
50 gr milk
35 gr butter
60 gr sliced cheddar cheese (around 3 pcs, cut into smaller pieces)

35g cake flour
15g corn flour
60 gr egg yolks
¼ tsp salt

75 gr egg whites
40 gr caster sugar
¼ tsp cream of tartar

1 tbsp parmesan cheese for sprinkle (optional)

Method :
- Preheated oven to 160C
- Melt milk, butter and sliced cheese using double-boiler method until thick. Remove it from double-boiler.
- While it still warm, add salt, shifted cake flour and corn flour, mix until well combined.
- While keep stirring, add egg yolks, stir until well combined. Set a side.
- Whisk egg whites, cream of tartar until foamy, add in sugar and continue whisk until soft peak form.
- Take 1/3 of white eggs batter to the cheese mixture, mix well.
- Then partially pour the cheese mixture to the remaining egg whites, mix until well combined.
- Pour into 10x30x4cm pan or 6” pan, wrapped outside with aluminum foil.
- Bake in water bath for 45 minutes or golden brown.
- Remove cake from the oven, and remove the cake from the mould immediately.
- Set aside to cool.