Put cauliflower in a saucepan and cook in salted water for about 8 minutes, then drain.
Melt the butter in a saucepan and dust the flour over it and sauté over a medium heat for about 2 minutes. Now sweat the curry powder briefly and deglaze with milk and chicken stock and stir until smooth. Simmer at a mild temperature for approx. 4 minutes. Season with salt, pepper and lemon juice. Now mix the potatoes, peas, ham and cauliflower and place in a greased baking dish. Pour the curry sauce over it and place in the oven preheated to 180 ° C and bake for 20-25 minutes.