| 1 | Put the onion into a heavy-based saucepan. |
| 2 | Add the stock and bring to boiling point very slowly so the onion begins to soften a little. |
| 3 | meanwhile coarsely chop a small handful (5 or so tablespoons) of lovage. |
| 4 | Add the potato and herbs to the pan and pour on ?pint buttermilk. |
| 5 | Increase the heat very slightly and bring the mixture to a bare simmer. |
| 6 | Stir vigorously all the while as the potato starch will thicken the soup, which may stick to the pan base. |
| 7 | Half-cover the pan and reduce heat as low as possible once again. |
| 8 | Cook very gently indeed, stirring occasionally, until the potatoes are perfectly tender. |
| 9 | whizz the contents of the pan to a smooth puree. |
| 10 | Season with salt and pepper and with extra lovage if you like. |
| 11 | Whizz again and thin to taste with a little more stock or buttermilk. |
| 12 | Reheat gently or chill thoroughly before serving, then garnish with a swirl of buttermilk and a small flotilla of chopped fresh lovage. |
