Separate the eggs, discarding the yolks. Place the egg whites in a medium-sized mixing bowl or the bowl of a stand mixer.

In a small saucepan over high heat, combine sugar, corn syrup, water, cream of tartar, and salt.

Bring the mixture to a boil, stirring occasionally until the sugar dissolves.

Remove the saucepan from the heat and set aside.

In the mixing bowl, beat the egg whites until soft peaks form.

While the mixer is running, carefully pour the hot sugar syrup into the mixing bowl in a very thin, steady stream.

Ensure the syrup hits the side of the bowl and runs down into the eggs to prevent cooking the eggs directly.

Continue mixing until the frosting turns glossy and begins to mound in the bowl.

The frosting should be stiff enough to form a peak with a slight loop at the tip.

Spread the frosting thickly over the cake using small, circular motions.

Twist a spatula or spoon on the frosting and pull up to form decorative peaks.

Create a slightly messy look to highlight the beautiful glossy peaks and valleys in the frosting.