Preheat the oven to 210'C.
Cut the butter into small pieces.
Place the water, sugar, salt and butter in a saucepan and bring to the boil. Once boiling, remove from the heat and mix in the sifted flour. Return to the heat and mix until the mixture no longer sticks to the bottom of the pan. Transfer into a food processor and beat in the eggs one by one. The mixture should be shiny and smooth and have a dropping consistency. You may not need to add the whole of the third egg. Place the mixture into a piping bag and pipe small circles on to a baking tray.
Brush the pastry with the egg yolk and sprinkle with the flaked almonds.
Bake the choux circles for 25-30 minutes.
Remove from the oven and allow them to cool. Once they are cooled cut them through the middle and lay upside down on a tray
Place the almonds on a baking tray and toast in the oven for 5 minutes to colour them. This will intensify the flavour.
Lightly beat the sugar, egg yolk and the whole egg with a tablespoon of the milk. Add the flour and stir well, making sure the mix is free of lumps. Bring the remaining milk to the boil, pour over the egg mix and combine. Return to the heat and cook until the mixture is thick and the flour is cooked. Remove from the heat and whisk in the butter. Add the toasted almonds and mix well. Once cool, place in a piping bag.
Pipe onto the bottom half of the Paris-Brest. When they have been piped, place the top half back onto the choux circles.
Sprinkle the Paris-Brest with icing sugar for presentation.
«For the first ten minutes of the cooking process do not open the oven door. This will prevent them from rising to full potential.»