Crack all eight eggs and carefully separate the yolks from the whites, ensuring no yolk mixes with the whites.

Line a 9x5 inch loaf pan with parchment paper, leaving an overhang on the long sides for easy removal.

In a mixing bowl, combine egg yolks, softened cream cheese, melted butter, salt, and vanilla extract if using, then blend on medium speed for 60 seconds until smooth.

In a separate clean and dry bowl, beat the egg whites on high speed until stiff peaks form, about 3 to 4 minutes.

Gently fold the whipped egg whites into the yolk mixture in two additions using a spatula and a folding motion until no white streaks remain.

Pour the batter into the prepared loaf pan and smooth the top with a spatula, filling the pan about three-quarters full.

Bake in a preheated 400°F oven for 28 to 32 minutes until the top is golden brown and a toothpick inserted into the center comes out clean.

Let the bread rest in the pan for 5 minutes, then transfer to a cooling rack and cool completely, about 15 to 20 minutes, before slicing.