I do a variation of the spinach one which is yummy.

I pkt frozen spinach
1 small jar mayo (whole egg is best) approx 300g
1 container sour cream
I pkt spring vegetable soup

Heat cob loaf in the oven until warm in the middle and crusty on the outside. While it is heating defrost the spinach and heat over the stove / in the microwave until warm. Mix together all ingredients in a bowl.
Remove cob from oven, cut off top (and keep). Pull out all the bread from the centre leaving a shell. Pour the spinach mixture into the cob. Use the warm bread from the middle for dipping and the lid to keep the mixture warm.
I usually cook a second cob because the bread *disappears* very quickly.