Bring the water with the vegetable stock to the boil. Add couscous, remove from the stove and, depending on the desired graininess, allow to swell, if necessary add a little more water and stir. I let it soak for at least 10 minutes.
Grease a baking dish with a little oil, add the couscous and smooth it out. Beat the egg and mix with the sour cream until a smooth mixture is formed. Season with salt, pepper and basil. Cut the tomatoes and mozzarella into slices. Then top the couscous alternately in flakes. Pour the sour cream and egg mixture over it and smooth it out. Sprinkle basil on top to taste and place in the oven preheated to 200 ° C. The casserole is ready when the mozzarella is golden brown and the sour cream and egg mixture is thick.
The casserole also tastes very good with oregano. It is very easy to prepare, tastes cold and warm. Due to the high mineral content of the couscous, it is also healthy and very suitable for pregnant women.