Mix together the egg yolks, sugar, milk, and pancake mix in a very large bowl until it is smooth with no large lumps.
2. Step
In another large bowl, beat the egg whites with a hand mixer until stiff peaks form when lifted.
3. Step
Carefully fold the egg whites into the pancake batter, until just incorporated, making sure not to deflate the batter.
4. Step
Grease two 3.5-inch (9 cm) metal ring moulds and set them in the middle of a pan over the lowest heat possible.
5. Step
Fill the moulds about ¾ of the way full with the batter, then cover the pan and cook for about 10 minutes, until the center of the pancakes are slightly jiggly.
6. Step
Release the pancakes from the bottom of the pan with a spatula, then carefully flip them over, making sure not to spill any batter inside.
7. Step
Cover and cook for another 5 minutes, then serve with butter, syrup, and berries!