Sides · Air fryer adaptation

Perfect Air Fryer Roast Potatoes: Crispy and Fluffy

Rick reckons the secret to perfect roast potatoes isn't duck fat, it's baking soda. A half teaspoon in the boiling water breaks down the starches on the outside, leaving you with crispy edges and fluffy centres every time, whether you're using an air fryer or oven.

R By Richard · Adapted from Backyard Chef · Published 10 June 2026
👁 80.4k source views ❤️ 2.6k source likes
⏱Prep 15 min
🌡Temp 200°C
⏲Air fry 25 min
🍽Serves 4
How to Make the PERFECT Roast Potatoes Fluffy Inside, CRISPY Outside

Source video by Backyard Chef on YouTube. This recipe was adapted with strict source-fidelity rules and is marked for human review.

This is Backyard Chef Rick's no-nonsense method for perfect roast potatoes every time. The trick is adding baking soda (sodium bicarbonate) to the boiling water, which breaks down the starches on the outside of the potato and leaves a fluffed-up edge ready to crisp. No fancy fats needed, just regular vegetable oil. The original video is an oven recipe, but the method translates directly to an air fryer because the science (broken-down starch plus hot oil contact) is identical. Adapted here for a domestic air fryer with timings and temperature adjusted accordingly.

Air fryer notes: Source cooks the potatoes in a tray in the oven at around 200-220°C for about 30 minutes (25 min on one side, then flipped and finished). Adapted to the air fryer at 200°C for approximately 25 minutes total with a turn at 15 minutes. Air fryer convection crisps faster, so total time is slightly shorter and the potatoes must be in a single layer, not overcrowded. Oil quantity reduced as less is needed to coat the basket than to fill an oven tray.

Ingredients

Main
  • 1 kgpotatoes, peeled and cut into large even chunks
  • 0.5 tspbicarbonate of soda (baking soda)
  • 3 tbspvegetable oil
Seasoning
  • rosemary salt
  • fresh rosemary, leaves picked (add late)
  • sea salt flakes (add late)

Method

  1. Peel the potatoes and cut them into large, roughly even-sized chunks.

    ~5 min

  2. Bring a pan of water to the boil and add the bicarbonate of soda. Carefully add the potatoes and boil for 7 minutes. Do not try to cook them through, you are just breaking down the surface starches.

    ~7 min

  3. Drain the potatoes into a colander and let them air dry for a minute. The edges should already look slightly fluffed and rough.

    ~2 min

  4. Tip the potatoes into a bowl and shake gently to fluff up the edges all over. This rough coating is what crisps in the air fryer.

    ~1 min

  5. Preheat the air fryer to 200°C. Add the oil to the basket (or a small air fryer tray) and heat for 1-2 minutes so the potatoes hit hot oil and start searing straight away.

    ~2 min

  6. Carefully add the fluffed potatoes to the hot oil and gently turn to coat. Season with rosemary salt. Spread in a single layer with space between them; do not overcrowd.

    ~2 min

  7. Air fry at 200°C for 15 minutes.

    ~15 min

  8. Turn the potatoes, trying to coat them in the oil in the basket. Add fresh rosemary now if using. Return to the air fryer and cook for a further 10 minutes, or until deeply golden and crisp to your liking.

    ~10 min

  9. Lift the potatoes out and let them sit for a minute so any excess oil drains away. Tip into a serving bowl, toss with a little more rosemary salt, and finish with a pinch of sea salt flakes for presentation.

    ~2 min

Frequently asked

Why add bicarbonate of soda to the boiling water?
It raises the pH of the water, which breaks down the starches and pectin on the outside of the potato. That gives you a rough, fluffy surface that crisps up beautifully when it hits hot oil. It is the single biggest trick for proper crunchy roasties.
Do I have to use a specific type of potato?
No. Rick is clear in the video that any potato will do. Maris Piper or King Edward will give a classic fluffy result, but the baking soda method works with whatever you can get hold of.
Can I use goose fat or duck fat instead of vegetable oil?
Yes, for flavour. The method itself does not need it though; plain vegetable oil gives you the same crispiness because the crunch comes from the broken-down starch hitting hot fat, not from what type of fat it is.
Do I need to preheat my air fryer?
Yes for this recipe. You want the oil in the basket hot before the potatoes go in, so they sear from the first second rather than soak. Two minutes at 200°C is enough.
Why are my air fryer roast potatoes not crisping up?
Usually one of three things: the basket is overcrowded so they steam each other, you skipped the bicarbonate of soda parboil, or you did not fluff the edges after draining. All three are needed for proper crunch.
Extraction notes (transparency): Source is an oven recipe but the method (baking soda parboil, hot oil, roast) translates cleanly to an air fryer. Specific potato weight, oil quantity, and salt quantity were not stated in the transcript, so sensible defaults are given and flagged. Air fryer time and temperature are adapted from oven values, not directly stated by the chef for an air fryer. | Second-pass critique flagged 3 fabricated and 5 quantified issues. See critique.issues for detail.