Melt the chocolate together with the water over the hot water bath. Mix in the sugar and milk, then add the egg yolks and beat the mixture heartily with a whisk. Remove from the water bath and beat over ice cubes until cold.
Beat egg whites together with sugar (2) until stiff peaks form and fold into chocolate mixture. Fill the quantity into buttered portion molds and bake in the oven heated to 180 degrees on the second lowest rack for about 20 minutes. The casserole must remain juicy inside.
In the meantime, boil the orange juice by 2/3. Add sugar and heavy cream and beat with a broom. Peel and pit the dates, cut them into thin strips and mix them into the sauce.
Fillet the oranges, put them in the sauce as a garnish and sprinkle with the chopped pistachios.
Dust the casserole with powdered sugar and cocoa powder and serve on the spot. Serve the sauce separately.
Tip: Do you prefer milk chocolate or dark chocolate? Depending on the case, use what tastes better to you.