Preheat oven to 350 degrees F.

Set out eggs to reach room temperature.

Grease or line an 8"x 8" square pan with parchment paper, or use wax paper to line the bottom of the pan.

Melt chocolate chips in a microwave-safe bowl. Stir the chocolate as it melts every about 40 seconds. Set aside to cool slightly.

Separate egg whites saving the yolks in another small dish.

Add egg whites to a medium mixing bowl and beat until medium peaks form. (Not stiff peaks)

Add one yolk at a time and beat until the mixture becomes glossy.

Whisk in the melted chocolate until completely combined.

Pour mixture into prepared cake pan.

Bake for 25 minutes or until the toothpick inserted comes out clean.

Let the cake cool in the pan on a wire rack.

When the cake has cooled frost if desired.