Preheat your oven to 180ºC/160ºC Fan, and line a muffin tray with large cupcake cases or muffin cases!
Prep your pumpkin (Or butternut squash) by peeling the vegetable, scraping out the seeds & stringy bits and then grating the flesh (like you would for a carrot cake), and squeeze the grated pumpkin with a towel so that a lot of the moisture comes out of the pumpkin - it releases a lot of water when baking and this will make it bake weirdly if you don't squeeze some of it out!
In a large bowl, mix together the self raising flour, light brown sugar, mixed spice, bicarbonate of soda, sea salt, and orange zest!
In a separate bowl, quickly whisk together the eggs, melted unsalted butter, and fresh orange juice.
Pour this into the dry mix and fold together until combined well.
Add in the sultanas and/or chopped walnuts, and then the grated pumpkin (or butternut squash) and mix so its all even - try not to overmix!
Spoon the mixture into the cupcake cases (I use a cookie scoop to make it even) and bake in the oven for 25-30 minutes (check at 22-25 minutes with a skewer and if it comes out clean they're done - just like a cake!). Leave to cool fully on the side.
Cream Cheese Frosting
Beat the unsalted butter for a couple of minutes so its really supple and smooth - gradually add in the icing sugar and milk so that it's a smooth buttercream.
Loosen the cream cheese slightly with a spoon then add to the buttercream - whisk for a couple of minutes, so that it's smooth and creamy!
Pipe your frosting onto your cupcakes and sprinkle with some halloween sprinkles! Enjoy!
Notes
You can use a regular buttercream for the topping if you wish - but I find the cream cheese flavour works really well with the pumpkin/squash flavour.
If you are not a fan of pumpkin, then the butternut squash will work out perfectly - the two are really interchangeable with each other so baking wise it doesn't make any difference - but it is VERY important to squeeze out any excess water before baking otherwise the sponge might not bake or will take a very long time!
Be careful when making the cream cheese frosting that you don't beat it too quickly, otherwise you will over mix it and the mixture might split or be runny - don't whisk it too quick!
These cupcakes will last in the fridge for 3 days, remove 30 minutes before eating so they're the perfect temperature, or you can freeze them for up to 3 months!