Peel the parsnips and cut them lengthwise into fry-sized sticks.
Put the fries into a large bowl of cold water and refrigerate for at least 1 hour or up to 8 hours.
Heat the tallow in a heavy bottomed pot to 325°F or until the oil bubbles around the handle of a wooden spoon. Careful, it’s hot!
Drain and pat dry the fries with a paper towel.
Work in batches to fry parsnips until they turn light gold in color, around 3 - 4 minutes.
Remove from the pot with a slotted spoon and drain on a paper towel.
When all the parsnips have been fried, increase the heat to 375°F and fry them in batches a second time. This allows the fries to get perfectly crispy.
Remove from oil, drain on a paper towel, and season immediately with sea salt and smoked paprika.
Snack, savor, and enjoy hot with the harissa mayo.
To make the Mayo:
Combine the red peppers, garlic, tomato paste, and spices in a small food processor.
Blitz until smooth.
Stir in the lemon juice and mayonnaise.
Season to taste with salt and store in the refrigerator.
Notes
You could also make your own mayo from scratch!Don't throw out your tallow -- you can use it a few times.