Cut the broccoli into florets, blanch for a few minutes in boiling salted water, drain in a sieve and rinse.
Mix the orange juice, vegetable stock and curry paste together. Cut the onion into wedges, finely chop the garlic and ginger. Sauté the onion in a deep pan until translucent, then add the garlic and ginger, sauté briefly and finally deglaze with the sauce. Bring to the boil and reduce the liquid a little, then turn the stove to low and add coconut milk. Stir until everything is mixed well. Season to taste with salt, pepper, chilli and curry.
Cut the fish into bite-sized pieces and add to the sauce with the broccoli. Let simmer over low heat without boiling until the fish is done.