Prepare the puff pastry dough and give it 6 turns. Roll the dough out to a thickness of 1.5mm and prick with a fork. Place the dough between two sheets of greaseproof paper, and two baking sheets, and bake in the oven at 180°C for approximately 7 min. When the pastry begins to change colour and is 2/3 cooked, use a serrated knife to cut out evenly sized 4 X 4 cm squares. Lightly brush the beaten egg* onto the pastry. Lower the oven temperature to 170°C and continue baking the puff pastry squares for approximately 5 min. Set aside in an airtight container with calcium chloride.
*for brushing on the dough
Creamy filling
Whisk together the half egg yolk, egg and whipping cream. Add the milk and season with salt, freshly ground white pepper and grated nutmeg.
Garnish
Cut the bacon into 5mm dice then pan fry in frothy butter. Once crisp, drain and cut into small dice. Leave to cool. Sweat the finely chopped onions in butter with the thyme. Chill in a blast freezer. Mix the diced bacon and onions with 1/3 of the creamy filling. Chill the square flexipan moulds in the blast freezer, spray with cooking spray then chill. Line the moulds with grated emmental then add the creamy filling that has had the garnish added to it. Using a piston funnel, fill the mould to the top with the remaining creamy filling. Cover with cling film and transfer to a steam oven, pre-heated to 90°C, for approximately 15 min. Chill in a blast freezer, freeze then remove from the moulds. Return to the freezer.
Sweat the finely chopped onions in butter, add the ham that has been cut into an 8 mm dice, then the cream. Cook until thick and creamy. Strain through a china cap sieve and, if necessary, correct seasoning with salt and freshly ground white pepper. Cool, place in a pipette and refrigerate.
Place the ham slices between two sheets of oiled greaseproof paper then position between two baking sheets. Bake in the oven, pre-heated to 170°C, for approximately 6 minutes, until just crisp. Whilst hot, cut into 2.5 cm x 1 cm triangles. Return to the oven until crisp. Finely chop the cured ham trimmings and set aside, along with the triangles, in an airtight container with calcium chloride.
Position the set creamy filling on top of a puff pastry square. Add the equivalent of a teaspoon of cream ham on top of the set creamy filling. Just before serving, sprinkle a few finely chopped cured ham trimmings around the edge of the set creamy filling. Decorate with a cured ham crisp and a chive tip.