Separate the eggs, keeping the yolks in their shells and removing as much of the whites as possible without breaking the yolks. Tip the whites into a large bowl. Prop up the shells with a scrunched up dish towel so they remain upright.
Preheat the oven to 180°C (gas mark 4 or 350°F)
Season the egg whites with salt, then whisk until they form very stiff peaks: they should be firm enough to withstand the weight of a small spoon without sinking in.
Liberally grease a tray with butter and pour the egg whites onto it in one fluid motion. Smooth out with a wooden spoon. Make 6 reasonably deep hollows a good distance apart, and then carefully place a yolk in each one. Season with pepper and then sprinkle with grated cheese and butter shavings.
Carefully place at the back of the oven. After about 30 minutes the top should be crispy and golden, and the yolks just set. Serve immediately. This simple dish is almost impossible to get wrong, but it cannot be allowed to stand.
Recipe courtesy of The Monet Cookbook: Recipes from Giverny by Florence Gentner, Francis Hammond (Photographer)