Cook the cauliflower florets (reserve a few for garnishing) in a large saucepan of boiling salted water for 3-4 minutes. Drain and allow to cool to one side.
Preheat the oven to 180°C.
Whisk together the eggs and milk with seasoning in a large mixing bowl. Stir in the cauliflower and chopped parsley.
Heat the olive oil in a large, heatproof frying pan over a medium heat. Pour in the tortilla mixture and allow the base to set before transferring to the oven to finish cooking for 5-7 minutes. Remove when totally set, then turn out and slice into square portions.
Arrange stacked on a serving plate and garnish with a sprig of parsley and the reserved cauliflower florets before serving.