In a small saucepan, gently heat half of the milk with the cocoa powder, whisking constantly to dissolve it fully and avoid lumps.
Once warm, add the chopped chocolate and stir until you have a smooth, glossy ganache. Set aside.
2. Prepare the custard base
In another saucepan, combine the remaining milk, the heavy cream, and the honey. Warm gently over medium-low heat, without letting it boil.
Meanwhile, whisk the egg yolks with the sugar and the cornstarch until pale and slightly thickened.
Slowly pour the warm liquid over the egg mixture, whisking constantly to temper the eggs. Then return the mixture to the saucepan.
Cook over low heat, stirring continuously with a wooden spoon or silicone spatula, until the custard thickens and coats the back of the spoon—about 180–183°F (82–84°C). Léonce's tip: To check if it's ready, dip a spoon into the custard, then draw a line across the back of it with your finger. If the line stays clean and doesn’t run, your custard is perfectly cooked.
3. Combine the two
Remove from the heat. Stir in the chocolate ganache.
Add a pinch of fleur de sel—it truly brings out the depth of the chocolate.
Cover with plastic wrap, pressing it directly against the surface, and let it cool completely—at least 3 hours, or ideally overnight in the refrigerator.
4. How to freeze without an ice cream maker
Pour the chilled mixture into a wide, shallow container.
During the first 4 to 6 hours, stir it every 30 to 45 minutes using a fork or whisk to break up any ice crystals and encourage a creamy consistency.
Notes
Makes about 6 to 8 servings—roughly 1 quart (0.9 L).