Kale (or green cabbage) with Leek

I nice change, this is from Madhur Jaffrey's World Vegetarian recipe book. She uses summer kale, I use winter kale or spring greens. For 4 servings -

2lb (900g) kale or green cabbage - washed, stalks removed and cut into 1/4in ribbons
1 good sized leek - washed well and cut into 1/4in slices
3 tablespoons olive oil
3 cloves garlic, peeled and cut into fine slivers
16fl.oz. (475ml) vegetable stock

Put the oil and garlic into a wide, medium pan on a medium heat. As soon as the garlic begins to sizzle, put in the leek. Stir and saut for a few minutes then put in the kale or cabbage. Stir once or twice. Add the stock and bring to the boil. Cover, turn the heat to low and cook until the leaves are tender. Season if necessary (this will depend on your stock). If there is too much liquid in the pan turn up the heat and boil it away, stirring as you do.