Separate the egg yolk from the white.

In a large mixing bowl add the egg yolk to the buckwheat flour, oil and salt.

Start adding enough water to mix to a firm batter, when the batter is smooth with no lumps incorporate the rest of the water.

In a small bowl whisk the egg white until it is peaking.

Gently fold into the batter and leave to rest for at least an hour.

When you are ready to cook your galettes, pre-heat a large non-stick frying pan (preferably a crepe pan) until it is very hot but not smoking, and pour a ½ cup or 120 ml ladle full of mixture into your pan. Tip the mixture around until it covers the pan evenly.

When the edges are starting to lift up from the pan, flip the galette over.

Lay a wide strip of smoked ham (about 7cm wide) down the middle and then sprinkle with Emmental cheese.

When the sides are just browning fold the two edges over the ham and cheese and continue to cook for another minute or two.

Turn over and cook for another minute or so until the cheese is all melted.

Transfer to a pre-warmed oven dish and keep in the oven at a low temperature (around 120°C/250°F) while you cook the other galettes.

When all the galettes have been prepared, enjoy!