Slice the top off the cob loaf and scoop out the inside leaving a 2cm edge and break it the bread into bite sized pieces. Arrange the hollowed out loaf and pieces of bread on a large baking tray and drizzle with olive oil. Bake for 10 minutes at 180°C until starting to get crispy.
While the bread is toasting melt the butter in a medium sized pot over a medium heat. Add the spinach and garlic and cook for about 5 minutes until spinach has cooked down.
Add cream cheese, sour cream, grated cheese and mix together. Cook for 5 minutes or so until smooth and creamy. Add salt & pepper to taste. If you think the dip is too thick, thin it out with milk or cream.
Remove the bread from the oven, pour the filling into the loaf and serve immediately!
You can also make the filling ahead of time and store in the fridge, reheating it on the stove before you need it.