Melt the butter in a casserole dish over a medium heat. Add the onions and garlic and sweat for 4-5 minutes, stirring occasionally. Add the remaining vegetables to the dish with the bay leaf and seasoning and cover with a lid.
Reduce the heat to low and allow the steam to cook the vegetables until just tender; roughly 10-12 minutes. Make sure you stir the vegetables every few minutes as they soften.
Meanwhile, pre-heat the oven to 180°C and prepare the crumble. Combine the cream cheese, flour and Parmesan in a large mixing bowl and rub together using your hands until they resemble coarse breadcrumbs.
Transfer the softened vegetables without the bay leaf to a 7 inch circular baking dish. Top with the crumble topping and bake for 25-30 minutes until it just starts to colour on top. Remove and allow to sit for 2-3 minutes before serving.