Whisk the eggs with the yoghurt, add a couple of pinches of salt.
Heat 1 Tbsp olive oil in a frying pan, add the egg mixture and tilt the pan to allow the mixture to spread around evenly.
Scatter the dill all over and turn down the heat.
When the omelette is half cooked, scatter the crayfish tails and spring onion bits on the top. Put a lid on and cook gently for about five minutes.
Take the lid off and cook further until the surface is just about to set, but no longer liquid.
Fold the omelette in half and cook for another minute or so. You can turn it over, if you like.
Slide it onto a plate, cut in half and serve with a green salad and/or piece of toast.