Wash the potatoes and cook in boiling water for about 20 minutes. Clean, trim and quarter the mushrooms. Peppers clean, wash and cut into strips. Clean, wash and cut spring onion into rings
Heat the oil in a pan. Fry the mushrooms for 2-3 minutes while turning. Add spring onions and bell peppers and fry for about 2 minutes, remove from heat. Wash parsley and shake dry. Pluck the leaves and chop them. Drain potatoes, rinse briefly with cold water, skin and slice. Wash spinach, drain
Place the spinach, potatoes, peppers, mushrooms and spring onions in a small greased casserole dish (approx. 300 ml capacity), sprinkle some parsley between each layer. Whisk eggs and milk, season with salt and pepper, pour over the vegetables. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 15-20 minutes until the egg mixture has set