To make the caramel, heat the sugar in an even layer in a frying pan until it melts and then starts to bubble to a golden brown. Swirl the pan if you need to keep the melting and browning even. Add a good-sized pinch of salt flakes and tip the caramel onto an oiled baking sheet set on a wooden board. Cool and then break into chips with a rolling pin. ( I used a meat pounder to break up mine)

Beat the butter and sugar in a food processor until you have a smooth paste. Add all of the flours and a pinch of salt and beat to form a dough. Tip onto a lightly floured board, pat out gently and sprinkle with the caramel chips. Fold in half and then transfer to a 20 × 30cm (or similar) tin and push into an even layer. Cover and chill for 30 minutes.  ( This did not work so well for me, so I cut it in half, pushed the first half onto an 8 x 12 cake pan, added the broken caramel, then patted the second half on top. – Worked great! )

Heat the oven to 180c/fan 160c/gas (350 ℉) 4. Bake the shortbread for 25-30 minutes or until golden brown and cooked through. Cool in the tin for 5 minutes, mark into fingers with a knife and then cool completely. Cut along the marked lines into pieces.  (I put a rack on top, flipped it out, then flipped it over with another rack.  Easy…  Used my biggest knife to cut right through)

Heat the chocolate in a bowl set over (but not touching) a pan of water or microwave until it starts to melt, stir until smooth and take it off the heat. Lay the shortbreads next to each other with a tiny gap between them on a cooling rack and spoon over the chocolate in strips and it doesn’t have to be perfect. While the chocolate is still wet, sprinkle with some salt flakes and then leave it to set. ( I used a piping tube to do it)

Here is what mine look like and they taste wonderful!