In a small mixing bowl or a cup, mix the baking soda with the soya yogurt and set aside.
In a large bowl, combine the pumpkin puree together with the 75g sunflower oil and 100g light muscovado sugar. Then stir in the remaining ingredients including the yogurt mixture until well combined.
Bake in a greased, lined loaf tin for around 35-45 minutes or until a skewer comes out clean.