Put the chopped onions into a pot with 2 cm / 2 inches of water, the garlic cloves, grated ginger, galangal and Thai green curry paste. Cook for 5-6 minutes until the onions are soft.
Add the sweet potato, carrot and cauliflower to the onions and mix well. Simmer with the lid on for 14 minutes, keeping an eye on it to ensure it doesn't catch on. Add some hot water to the pot if you like a more sauce.
Add the Tenderstem broccoli to the pot and cook for a further 5 minutes.
Add the spinach to the pot and stir in for 1 minute until the spinach has wilted.
Serve onto warm plates.