You may also make the desert chocolate. Just mix the egg yolk with sugar, vanilla sugar and a 1/2 tsp of chocolate-instead of lemon juice.
The best eggs for this are of course from the farm, I buy mine from my local farmer, not from the store. The yolks are orange and healthy. I see the chickens run and peck around the farm looking healthy and happy, every time I go there. They also taste so much better, than store bought. They taste like the eggs from my childhood.
Try to find a farmer in your area and take your kids for a weekend drive. They will love it.