Heat the butter in a thick-bottomed saucepan. Stir in the chopped onion and the rice until well crispy. Wet with the spirit and let evaporate. In the meantime prepare a light stock using vegetable cubes and/or carrots, tomatoes, celery and one potato. Chop the salmon in thin strips.
To make the risotto: add the hot stock, ladle by ladle having the patience to wait for the liquid to be absorbed while you keep stirring vigorously. When it is nearly done – taste it until you get the right texture! – adjust the seasoning. Switch off the heat and throw in the salmon.
Leave the risotto to ‘stew’ for a few minutes off the heat before serving.