Soak the chickpeas in cold water overnight.
Simmer the chickpeas with a pinch of salt, black pepper, a drizzle of olive oil, herbs and the trimmed vegetables. Once cooked let the chickpeas cool down in their own water. Discard the herbs and vegetables.
Blend some of the chickpeas with a bit of cooking water to obtain a purée to be used as base for the fish fillets and keep warm.