Preheat the oven to 180c/350f.
Add all of the ingredients to a Blender jug and blend until smooth (~ 30-60 seconds).
Pour into muffin liners, top with optional choc chips then bake for 25-27mins until a skewer comes out clean.
Remove from the oven and allow to cool in the tin for 5 minutes, then leave to cool on an airing rack (if you are using silicone removable liners, remove from the liners to avoid them becoming stodgy as the moisture gets trapped in).
Store in the fridge for 5 days or freezer for 2 months