Preheat the oven to 400F (200C)
Place the cashews in a small bowl and add some boiling water. Leave soaking for about 20 minutes. Drain, rinse and set aside.
¾ cups cashews
While the cashews are soaking, wash the red pepper, place it on a small casserole or baking dish, make some small holes with a knife or fork, and bake for about 30 minutes or until the skin is charred.
1 red bell pepper
Leave to cool and remove the skin and seeds.
While the red pepper is roasting and the cashews are soaking, you can cook the pasta following the package instructions. Use salted water to cook the pasta al-dente and before draining the pasta, save some pasta water for later.
14 oz spaghetti pasta
Drain the pasta, add some olive oil so it doesn't stick easily, and reserve.
Heat some olive oil in a small pan over medium heat, and add the onion finely chopped.
1 onion
Stir and cook until it softens. Then add the garlic, finely sliced, cook for another 3-4 minutes, and turn the heat off.
2 garlic cloves
Add to a blender jug the soaked cashews, the roasted red pepper, sautéed garlic and onion, harissa paste, lemon juice, and vegetable stock or water.
¾ cups cashews, 1 red bell pepper, 1 onion, 2 ½ tablespoon harissa paste, lemon juice from ½ lemon, 1 cup vegetable stock or water, 2 garlic cloves
Blend until the cashews are perfectly blended and you have a smooth sauce.
Combine in a pan the pasta and sauce, and add crushed pistachios, finely chopped sun-dried tomatoes, and fresh oregano or parsley.
A handful pistachios, 3-4 sun-dried tomatoes, A handful fresh oregano
Mix well, add some reserved pasta water if needed, and serve.