Preheat your oven to 220°C/200°C fan/gas mark 7.

Chop the potato and sweet potato into 2cm chunks (no need to peel). Pop them both onto a large baking tray. Drizzle with oil, season with salt and pepper, then toss to coat.

Spread out in a single layer. TIP: Use two baking trays if necessary.

When the oven is hot, roast on the top shelf until golden, 25-35 mins. Turn halfway through.

Zest and halve the lemon. Finely chop the chives (use scissors if easier). Discard any tough stalks from the cavolo nero. 

Peel and grate the garlic (or use a garlic press).

In a small bowl, combine half the chives, half the lemon zest, a squeeze of lemon juice and the olive oil (see pantry for amount). Season with salt and pepper, then set aside.

Pat the salmon dry with kitchen paper, then season with salt and pepper. Sprinkle over the Cajun spice mix over the salmon and season with salt and pepper.

Rub to coat, then set aside for later. IMPORTANT: Wash your hands and equipment after handling raw fish.

Heat a drizzle of oil in a large frying pan on high heat. Add the cavolo nero and a splash of water and cover until wilted, 3-4 mins.

Remove the lid, add the garlic and stir-fry for 1 min more. Season to taste with salt and pepper. Transfer to a large bowl and cover to keep warm.

Wipe the frying pan clean with some kitchen paper - you'll use it to fry the salmon.

When your potatoes have 10 mins remaining, put your (now empty) frying pan on medium-high heat with a drizzle of oil.

Once hot, carefully place the salmon into the pan, skin-side down. Cook for 4-5 mins, then lower the heat to medium. TIP: To get crispy skin on the fish, don't move it around when it's cooking skin-side down.

Turn and cook the remaining three sides for 2-3 mins each. IMPORTANT: The fish is cooked when opaque in the middle.

When the potatoes are cooked, add them to your bowl of cavolo nero and roughly mash. Stir through a knob of butter (if you have any) and the remaining chives. Season with salt.

Share the salmon between your plates. Drizzle over the chive dressing.

Serve the mash and a dollop of mayo (see pantry for amount) alongside.