Melt the cream cheese, butter, and milk over low heat, stirring until smooth. Remove from heat, whisk in egg yolks, then sift in the flour and cornstarch until combined.

Beat egg whites and lemon juice until foamy, gradually add half the sugar, and whip to stiff glossy peaks.

Stir a scoop of meringue into the base to loosen it, then fold in the rest gently until no streaks remain.

Pour into a lined 6-inch round pan, place in a water bath, and bake at 160°C (320°F) for 60 minutes. Turn off the oven, let it rest 15 minutes, then crack the door and cool 30 minutes.

Cool completely at room temperature, run a knife around the edge, unmold, and slice.