Step 1

Heat the butter in a non-stick frying pan over a low-medium heat and gently fry the onions with a pinch of salt for 10 minutes until softened. Tip into a large bowl and cool. Whisk in the eggs, flour, cheddar, mustard and plenty of seasoning, then gradually stir in the milk until you have a thick batter.

Step 2

To make the salad, whisk together the shallot, vinegar, mustard, oil and a little seasoning in a separate bowl.

Step 3

Heat a knob of butter in a non-stick frying pan and drop in 2-3 heaped tbsp of batter. Cook for 2-3 minutes or until golden, then flip and repeat. Put the cooked fritters on a baking tray and keep warm in a low oven while you cook the rest (you should get about 12).

Step 4

Add the watercress and parsley to the dressing just before serving, and toss well. Divide the leek fritters between plates and serve alongside the salad.