Pasta with potatoes is a typical Neapolitan recipe of the seventeenth century. The first historical sources of transcription of this dish are found in Vincenzo Corrado's book The Cook Galante (1773).
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The dish has numerous variations (with pancetta, with tomato, with parmesan crusts, dry or in the form of soup) and traditionally it was made with "pasta ammischiata", or with various types of mixed pasta (to remember that it is a poor recipe, made with recycled products).

My version of pasta and potatoes is quite different from the original because I reduced the portion of sauté to a minimum and used a creamy cashew to increase the soft and enveloping part of the potatoes, compensating for the absence of parmesan, provola or other flavoring of animal origin.

320 gr of mixed pasta or short pasta
4 small red potatoes
1/2 leek
100 gr of cashews
2 cloves of garlic
1 handful of parsley
1/2 lemon (juice)
salt, pepper, extra virgin olive oil

Soak the cashews for 3 hours.

Wash, peel and dice the potatoes. Put them in a pot to boil in abundant salted water (where you will also boil the pasta).

Drain the cashews and blend them with a blender together with the lemon juice, 1 pinch of salt and 1 clove of garlic.

When the water with the potatoes boils, pour the pasta and cook it.

Chop the leek and 1 clove of garlic. Put them in a wok and brown them for a couple of minutes with 4 tablespoons of oil. Add the pasta and potatoes once drained and the cream of cashew nuts. 

Mix well, grate some black pepper and sprinkle with parsley before serving hot.