
These are one of my favourite ways of preparing potatoes. They are oh soft on the inside and crunchy on the outside. They remind me a little of those hash brown patties from a fast food breakfast menu – without the oily mess.
Both air fryer and oven cooking methods are included in the instructions. Both methods yield crispy fries it’s just that the oven method takes quite a lot longer which requires more patience.
You will need to prepare your mashed potato brick ahead of time to let the brick chill in the fridge overnight.
Enjoy and please take a photo of your Crispy Mashed Potato Fries tag me on Instagram @potato.wisom

Crispy Mashed Potato Fries
Equipment
- Pressure Cooker or Large Pot
- Air Fryer or Oven
Ingredients
- 5 lbs potatoes (white, russet or red)
Optional Spices
- 1/4 cup nutritional yeast (optional)
- 2 tsp onion powder (optional)
- 2 tsp garlic powder (optional)
- 2 tsp smoked paprika (optional)
Instructions
Mashed Potato Brick (make the day before)
- Wash potatoes (scrub any dirt off) and rinse. Peeling isn't necessary but if you prefer that, go ahead.
- Pressure Cook Method: Place whole potatoes directly in pressure cooker pot without trivet. Pressure cook on high for 11-12 minutes, let naturally release for 10 minutes. Drain water – reserve about a half cup of the cooking water in case you need it for mashing.
- Boil Method: Quarter potatoes and place in a large cooking pot, put in enough water to submerge all the potatoes. Boil until soft (test with a fork). Drain water – reserve about a half cup of the cooking water in case you need it for mashing.
- Add optional spices if you want some extra flavor. These are good with our without so this is totally optional. Most of the time I make mine plain.
- Mash with a hand masher until mostly smooth. Use a smidgen of the cooking water if it helps you mash easier. You want to keep the liquid minimal. It's okay if there are some small chunks.
- Transfer mash potatoes into a square or rectangular food storage container. Firmly press into container. Let cool to room temperature without lid.
- One cooled you can store in the fridge overnight with the lid on.
The Next Day – FRIES!!!
- Remove the lid from your mashed potato container and quickly and firmly place upside down on a cutting board. It may take a couple of firm quick drops onto the cutting board to get it to come loose.
- Once loose, slide the container up to separate. Behold the glorious mashed potato brick.
- Using a large sharp knife, cut into steak fries or nugget sized squares (toasties). Whatever floats your boat.
- Oven Method: Line a baking sheet with parchment paper or silicone cooking mat. Bake at 425°F for 40 minutes, flip and continue baking for another 20-30 minutes or until desired crispness.
- Air Fryer Method: Air fry at 400°F for 20 minutes. Add 5 minute increments if needed to reach desired crispness,
Troubleshooting Soggy & Burnt Fries
- Got a Soggy Mashed Potato Brick? If you ended up with a soggy mashed potato brick, you either used too much liquid in the mashing process or overcooked them. Don't throw it away, you have a few options. 1. Reduce your cooking temperature and cook for longer to help dry it out. The crunch comes from cooking out the moisture. 2. If it's too far gone and a soggy mess – convert it into a soup! Add some veggies, broth, onions, garlic, and blend until smooth or use as a base for potato cheese sauce.Burnt on the Outside but Soggy on the Inside? Reduce your cooking temperature (oven 350°F) (air fryer 300°F), cook for a longer period of time. Once they are starting to look slightly golden on the outside: up the temperature according to the original instructions and continue cooking until crisp on the outside.