Wash the cabbage well and cut the leaves away from the stalk. Cut the lengths into rough 2 cm or 1 inch pieces.

In a large saucepan, over a medium heat, add 2 cm or 1 inch of boiling water and add the kale. Put the lid on the pan and allow the kale to steam for about 5 minutes.

While the kale is cooking melt the butter in a small pan over a medium heat. Once it has melted, continue to heat it until it becomes foamy. At this point watch the butter closely as the foam subsides. Small brown specks should appear and the butter should have a nutty aroma.

Tip the crushed garlic into the butter and then immediately pour the butter mixture into a bowl to stop it from cooking further. Now add the lemon juice to the butter to make the beurre noir.

When the kale is cooked drain over a colander and return to the saucepan.

Immediately pour over the beurre noir and stir through.

Serve with the lemon zest sprinkled on top.