Somewhere between a roast potato and crunchy fries, these are very good potatoes.
Peel the potatoes and cut a small slice off the back of each one so they stand up sturdily. Take a very sharp knife and cut a series of parallel lines along the length of the potato, going almost all the way to the bottom, then flip 90° and repeat to get a cross hatched effect. Wash the potatoes in cold water to remove as much of the starch as possible.
Place the potatoes in a large saucepan and cover them with cold water. Add a good heaped tbsp of salt. Bring to a simmer and cook for roughly 15 minutes or until par cooked. Leave to steam dry!
Meanwhile, grind the garlic cloves to a smooth paste. Pop this paste in a large glass mixing bowl and stir through the mustard and vinegar. Use an electric whisk (unless you have strong arms and you're a masochist) and slowly drizzle in the oil, whisking constantly. The alioli will start to thicken. If it looks greasy or like it'll start to split, add a splash of water. Season to taste.
Heat the oil in a large heavy bottomed saucepan until it reaches 140°C. In batches, fry the potatoes until they are cooked through with a light golden crust. Remove them from the oil, drain on some towels and use a knife to prize apart the cuts, otherwise they won't fan out to make the pom pom effect.
Crank up the oil to 180°C. Fry the potatoes in batches until they are super crispy, another 5 - 10 mins. Serve with the alioli.
