Heat the milk to between 110˚F and 113˚F (approx. 45˚C) in a medium pot over medium heat.

Pour the milk into a large heatproof bowl and sprinkle the yeast over it. Let it sit for 10 minutes.

Meanwhile, place the flour, sugar and then the butter in the bowl of a food processor fitted with a metal blade. Pulse eight to ten times.

Tip the flour/butter mix over the warmed milk and use a wooden spoon to just incorporate the dry ingredients into the milk.

Use your hands to form a ball of dough. Cover the bowl tightly with plastic wrap and place it in the fridge for at least 1 hour.

Remove the dough from the fridge and lightly flour your countertop. Knead the chilled dough gently until you can feel it becoming softer.

Lightly flour a rolling pin and roll out the dough until you have a very large rectangle (8 x 17 inches/20 x 40 cm).

Fold the top of the dough about two-thirds of the way down, then fold the bottom third up over the first fold.

Turn the block of dough clockwise so the seam is on your right. Repeat Steps 7 through 9 seven times for a total of eight 'turns.'

Wrap the dough tightly in plastic wrap and refrigerate for a minimum of 3 hours, but preferably overnight.

Line two baking trays with parchment paper. Roll the dough until you have a rectangle that is a little over 8 x 24 inches (20 x 60 cm).

Make a small cut in the dough on each side of the rectangle every 4-½ inches (12 cm). Cut a rectangle across the width of the dough.

Cut each rectangle in two diagonally to make two triangles. You'll have 10 triangles.

Gently stretch one of the triangles at each corner, then roll up the dough until you have reached the pointed end.

Place five croissants on each tray and cover each tray with a clean tea towel. Leave to rest in a warm place for 3 hours.

Preheat the oven to 375˚F (190˚C). Whisk the egg and cream together and gently brush the tops of the croissants with this egg wash.

Bake for 20 to 25 minutes, or until the croissants are golden brown on top. (Note: DON'T switch the trays from top to bottom and turn them from front to back halfway through baking EVEN THOUGH THE BOOK SAYS SO. Bake them a tray at a time if need be.)

Let the croissants sit on the baking trays for about 10 minutes, then place them on a wire rack to cool completely.