Courgette and carrot gratin
Heat the butter over medium high heat until foaming. Add the onions.
Turn the heat down to low and cook, without colouring, for about 10 minutes until very soft.
Tip in the carrots and courgettes. Cook and stir until the courgettes are beginning to wilt.
Sprinkle the flour over all and stir.
Mix the milk and stock together and then slowly pour this over top, stirring gently and cooking until it thickens.
Season to taste with some salt and pepper.
Preheat the oven to 200*C/400*F/Gas mark 6.
Butter a shallow gratin dish. Pour the courgette mixture into the gratin dish.
Mix together the bread crumbs and the gruyere cheese. Sprinkle this mixture evenly over top of the vegetables.
Bake for 25 to 30 minutes, until bubbling and lightly browned on top.
Allow to sit for about 10 minutes before spooning out to serve.