Difficulty: Medium
Preheat the oven to 210°C (thermostat 7). Wash the potatoes thoroughly and arrange them on a baking dish lined with coarse salt. Bake for 35 minutes until tender.
Separate the egg yolks from the whites, then whisk the whites to stiff peaks. In a saucepan over low heat, melt the butter with half the crumbled Roquefort. Stir in the flour and cook gently to form a roux. Gradually whisk in the boiling milk to create a smooth sauce. Add the egg yolks two at a time, along with the cayenne, nutmeg, and remaining Roquefort. Season lightly with salt, then gently fold in the egg whites using a lifting motion to keep the mixture airy.
Remove the potatoes from the oven (keep it on). Slice off the tops and scoop out the interiors without breaking the skins. Wrap each potato with a slice of ventrèche, securing with kitchen twine. Fill generously with the Roquefort mixture.
Return to the baking dish and bake for 25 minutes, until the filling puffs up and turns golden. Serve hot for the best texture and flavor.
