Preheat the oven to 200°C.

Make the frangipane by beating the ground almonds, butter, caster sugar, almond extract and the yolk only of the egg to make a thick paste. Reserve the egg white for now in a small bowl.

Roll out your pastry to a rectangle about 12×14 inches in size using as little extra flour as you can. You don’t need to be exact just don’t roll your pastry too thin – around 5 mm is ideal.

Trim the edges to get them square and reveal the layers of puff. Cut 5 long triangles out of the rectangle, gently bringing the trimmings together and rolling out to a rectangle, again just trimming off a tiny amount to neaten up. This one will be the cook’s perk – as long as you didn’t handle it too much, it should puff almost as well as the triangular ones.

Spread the cut out shapes with the frangipane leaving 2-3mm gap around all edges and on the triangles, stop short of the top 2inches or so to help get a seal and neat finish when you roll up.

Starting at the widest edge, roll up the croissant keeping a little tension on the pastry. Don’t stretch it or this will hamper the rise on baking. Classically, almond croissants are left straight whereas plain, all butter ones are curved into that “crab” like shape.

Beat the reserved egg white till frothy then brush the croissants trying not to drip down the cut edges, again as this would impair the rise. Sprinkle with the flaked almonds and bake for 15-18 minutes until golden and well risen.If any frangipane has escaped on baking, loosen with a palette knife and trim away as it will catch in the hot oven and be bitter to taste.

Transfer to a rack and dust heavily with icing sugar before serving.