Toast the cashew nuts in a dry pan on a high heat until golden (see photo). Reserve a few for garnish.

Wash the Thai basil and take leaves off the stalks.

Place all ingredients (minus the pasta and reserved cashew nuts) into your pestle & mortar (or food processor if using - see ‘cooking notes’). Grind or blend until you have a coarse texture (see photo). If you are using a pestle & mortar, you may have to add the herbs a bit at a time so that it all fits.

Taste and adjust the seasoning with salt and pepper.

Cook the pasta according to packet instructions or until al dente. Do not oversalt the water as you will be using a lot of it in the final step (I recommend 1.5 tsp of salt per litre of water).

Once al dente, drain the pasta and reserve one mug of the cooking water.

Tip your pasta back into the warm pan and add your Thai basil pesto. Add a drizzle of olive oil and a quarter of the water. Keep mixing and adding water if needed until the pesto is well-mixed and you have an oozy consistency. It is good if you have a small pool of ‘creamy’ sauce at the bottom (see photo).