Thoroughly wash the potatoes and cook them in a plenty of water until they are soft, around 25-30 minutes.
Meanwhile prepare the pesto: Mix the basil, parsley, parmesan, cashews and garlic with the olive oil and chop it up with a stick blender or a food processor. If it seems too dry, add a splash of olive oil.
Add salt and pepper to taste, set aside.
Wash the asparagus and cut them into into 1.5inch / 4cm sizes pieces.
Drain the potatoes and leave them to cool down for 10-15 minutes.
Meanwhile heat a non-stick pan over medium to high heat and add some olive oil. Add the asparagus and fry them, until they are slightly brown on the outside and tender on the inside (cook them to your taste actually… if you like them firmer, go for that.)
Cut the potatoes into chunks, place them in a big bowl and mix them with the fried asparagus and the spring onions.
Dress the potatoes with the pesto and add juice and zest of one lemon.
Adjust the seasoning if necessary.
Serve warm or cold.