Wash the leeks thoroughly and slice them down the middle lengthways.
Heat the oil in a large pan and add the leeks, cut side down to the pan. Brown them for 2 minutes each side and season with pepper.
Add the stock to the pan, and gently bring the liquid to simmer, reduce the heat to low and cover with a lid to cook for 10 minutes or until the leeks are tender.
Remove the leeks and set aside.
Preheat the grill.
Return the pan to the heat, increase the heat and reduce to half the quantity.
In a food processor, blend the pinenuts with the chopped sage.
Return the leeks to the reduced stock. Sprinkle the pinenut and sage mix over the top of the leeks and place the pan under the grill.
Grill until the pinenut mix toasts slightly taking care not to burn them.
Note: Leeks collect dirt between their layers of tubular leaves. To clean, cut the woody dark leaves off then using a sharp knife make a 10cm vertical slice halfway through the cut side of the plant. Fold the leaves out like a fan and hold it under running water to wash out any trapped dirt.
Makes 4 servings (serve = side dish)