Put the rice on top with 1/2 liter of water and a little salt and cook for 30 to 35 minutes.
Thaw the spinach leaves according to the instructions on the package, season with salt, pepper and nutmeg. In the meantime, whisk the whipped cream with the egg and season with salt, pepper and nutmeg. Grate the cheese or cut it into fine cubes. Put the finished rice in a greased casserole dish, sprinkle about 50 g of cheese over it and pour half of the cream sauce over it. Then layer in the spinach, sprinkle about 50 g of cheese on top and pour the rest of the cream sauce on top. Place the casserole without a lid in the oven for 10 minutes at 180 ° C (convection 160 ° C) (middle rail). Then sprinkle the rest of the cheese on top and bake for 10 minutes under the grill.