Cut butternut squash in half exposing the seeds inside and scoop the seeds out. Place them on a foil or grease proof paper and drizzle one teaspoon of sesame seed oil on top, and sprinkle some a third of the onion salt and mixed spice.
Rub oil and spices into the seeds and place the tray in oven for 5 minutes, making sure they don’t brown too much.
Cut the rest of the butternut squash into chunks and add the rest of the sesame oil and spices rubbing all over the butternut.
Place in oven for 30 minutes (the smaller the chunks the less cooking time). To test if they are ready, you can pierce a folk and if it goes all the way through with ease, the squash is ready.
Let butternut cool for 5 minutes and then scoop out flesh with spoon or peel off skin with your hands or knife.
Put all contents into a food processor with a table spoon of sweet tahini, and blitz until chunky ( avoid making into purée) or alternatively you can use a potato masher making sure the sweet tahini is fully incorporated.