Melt butter and blend with milk

Add flour and corn flour

Whisk in the egg yolk one at a time and set aside.

On a sepate bowl, whisk the white eggs together with salt

Slowly add the white sugar and whisk until it forms stiff peaks

Fold in approximately 1/3 egg whites to the batter

Fold in the batter to the egg whites

Transfer to the prepared pan and bake at 150° celcius for 90 minutes on a water bath