For the dough:
3 tablespoons of sugar
1/2 teaspoon baking powder
Mix together and spread evenly in the baking dish.
Add the washed, peeled and dices rhubarb (make sure it’s not too wet anymore). Put into the oven at 200°C for 15 minutes.
For the topping:
Mix together one egg (you can take some of the egg white away, since the mixture risks to become too runny) with a little cream and one tablespoon of sugar.
After the first 15 minutes of baking pour this mixture over the “tarte” and bake for another 15 minutes.
If you choose to not add this egg/cream mixture, your “tarte” will also need around 30 minutes in the oven and turn out quiet nice only slightly drier.