5 egg yolks
juice of 1 lemon
1/2 teaspoon cayenne
1 teaspoon salt
1 teaspoon sugar
1 stick unsalted butter, cut into tablespoon-size chunks
Place an inch of water in the pot, cover and bring to a boil.
Place the egg yolks in the metal bowl and whisk vigorously until they lighten in texture and colour. This is important, as it partially denatures the proteins in the yolks, which will prevent them from curled when faced with the lemon juice.
Add 2 teaspoons of the lemon juice, 1/4 teaspoon of the cayenne, a pinch of salt and all of the sugar. Whisk until smooth.
When the water boils, reduce the heat to medium low and place the bowl on top of the pot.