1 puff pastry sheet, thawed
1 large sweet onion, quartered and cut in thin slices
2 medium leeks, cut in thin slices
60 g ham or speck, cubed
2 eggs, separated
1 1/2 cups Emmental cheese, grated
125 ml/1/2 cup whipping or heavy cream
pepper, to taste (fresh ground)
How to make:
Preheat oven to 350-400º F (175-200º C). Adjust rack to middle of oven.
Line 11"/28 cm springform pan with puff pastry.
In a large bowl, mix together sliced onions (or leeks), cubed ham, egg yolks and grated Emmental cheese. Add cream and mix to combine. Season to taste with pepper (adding salt is not necessary - ham and cheese provide enough salt).
Whisk egg whites until stiff. Fold them gently into onion mixture. Pour filling in springform pan and smooth surface with spatula.
Bake at 350 - 400 F for about 30 minutes, until crust is done, and filling golden brown.
My friend Andrea Simms from Hamburg gave me this recipe.