Preheat your oven to 300 degrees Fahrenheit. Line a baking sheet with parchment paper and set aside.

Carefully separate the egg whites from the yolks, ensuring no yolk gets into the whites. Place whites in a large mixing bowl and yolks in a separate small bowl.

Add cream of tartar and salt to the egg whites. Using an electric mixer, beat on high speed until soft peaks form. Gradually add 2 tablespoons of sugar and continue beating until stiff, glossy peaks form, about 3-4 minutes.

In the small bowl with egg yolks, add the remaining 1 tablespoon sugar, cornstarch, and vanilla extract. Whisk until smooth and well combined. Add food coloring if desired.

Gently fold the yolk mixture into the beaten egg whites using a spatula. Use a folding motion to maintain the airiness, being careful not to deflate the mixture.

Spoon or pipe the mixture onto the prepared baking sheet in 4 equal mounds, creating cloud-like shapes. Bake for 23-25 minutes until the tops are lightly golden and set.

Remove from oven and let cool on the baking sheet for 5 minutes before transferring to a wire rack. Serve immediately for best texture, as cloud bread is best enjoyed fresh.