Preheat the oven to 356F/180C.
Line and grease a baking tray with parchment paper and set aside.
Before you begin, make sure the pumpkin is clean so wash and blot it dry.
Slice the pumpkin into half, do so by using a chefs knife and slice from the top(not the stem as it will be too tough) ,holding onto one half of the pumpkin to prevent it from moving and wiggle the knife to slice through.
Use a spoon to scoop out the pumpkin seeds (you can save them and roast them another time.
Place the pumpkin halves face down on the baking tray.
Coat the top of the skin with olive oil.
Roast the pumpkin until the skin is soft and tender (it should prick with a fork with ease) (this should take around 40-60 minutes depending on the size) don't worry about any brown spots, it won't impact the end result.
Once the pumpkin is ready, remove it from the oven and leave it until it is cool or safe enough to handle.
Use a spoon to scoop the flesh from the skin (discard the skin).
Transfer the puree to a food processor or alternatively place in a medium sized bowl and use a hand held stick blender and puree into a smooth consistency.