Heat the oil in a large pan, then add the leeks and garlic and cook for 10 minutes.
Dissolve the stock cube in the water then add to the pan with the herbs and simmer for 10 minutes. Add in the Creamy Sheese, milk and cornflour and continue stirring until thickened.
Stir in the spinach leaves and butter beans and heat through, then remove from the heat and tip into an ovenproof dish.
Mix together the flour, oats, sunflower seeds and herbs in a bowl. Rub in the spread with your fingertips to form a crumble mixture. Scatter this over the butter bean mix to cover then sprinkle over the grated Sheese.
Bake for 20-25 minutes until golden and bubbling – then serve!