Can I freeze muffin mixture? I am making these muffins but would like to freeze half the mixture - will this be ok or will it affect how they cook/rise/taste when I cook my second batch (from the frozen mixture)?

(Recipe contains - self raising flour, bicarb soda, golden caster sugar, chocolate, dried cranberries, butter, eggs, yoghurt)
Muffins are a quick bread, same as waffles, so the answer to Can you freeze waffle batter? applies equally well here.

You can freeze it, and it will keep the batter from spoiling, but it will not maintain the quality.  It won't rise very well when you thaw it and try to bake it.

I would suggest that instead, you freeze the wet and dry ingredients separately; measure them out into the portion sizes that you intend to use, and when you want to make more muffins, combine them after thawing them.

(Or, as Joe suggests - just freeze the finished muffins themselves.)