Boil the potato in salted water for 20 minutes until tender and mash until smooth.
Preheat the oven to 180°C.
Sauté one chopped garlic clove in oil, then wilt the spinach and season with salt, pepper, and lemon juice.
Beat the eggs in a bowl and stir in the spinach mixture, chopped herbs, and spring onions.
Whisk in the remaining garlic, cardamom seeds, and additional seasoning.
Combine the egg mixture with the mashed potato.
Melt the butter in a 25cm ovenproof frying pan to coat the bottom and sides.
Pour in the mixture and bake for 30 minutes until the center is set.
Cool for 10 minutes before slicing and serving.