Thinly slice the onion. Cut the tomatoes into 2cm chunks. Halve the unpeeled potatoes, then slice into 1cm-thick rounds. Pick the parsley leaves, then finely chop the stems. Crush or finely chop 2 garlic cloves.
Step 2 — Soften onion
Heat 2 tsp olive oil in a medium deep frypan over medium heat. Cook the onion, garlic and parsley stems, stirring occasionally, for 4-5 mins until softened. Add 1 tsp Cajun seasoning and cook, stirring, for 30 secs or until fragrant. Season with salt and pepper.
Step 3 — Make crazy water
Add the tomato, potato and 625ml (2½ cups) water to the onion mixture and bring to the boil. Reduce the heat to medium and cook, covered, stirring occasionally, for 13 mins. Uncover and cook for a further 5 mins or until the potato is tender. Remove the pan from the heat. Season generously with salt and pepper.
Step 4 — Pan-fry fish
Meanwhile, combine the remaining Cajun seasoning and 2 tsp olive oil in a large bowl and season with salt and pepper. Add the fish and turn to coat. Heat a medium frypan over medium heat. Cook the fish for 3½-4 mins each side until browned and cooked through (to test the fish, flake with a fork; if it comes apart easily, it's cooked). Remove from the pan.
Step 5 — Serve up
Divide the crazy water among bowls and top with the fish. Scatter over the parsley leaves and enjoy!
Step 6 — Did you know?
'Crazy water', or 'acqua pazza' as it's known in Italian, is a light, fresh, tomato-based broth used as a poaching liquid for seafood. Here we've pan-fried the fish separately for a golden finish and dialled up the 'craziness' with our Cajun seasoning.