Will eating half frozen pancakes make you fat?

Yes, but not because they are frozen. It's more because they are made with white flour, which has a lot of carbohydrates but not much of any other nutrition. Fry some eggs instead.

Put dab of butter on a waffle iron. When it melts, crack an egg into the puddle, put some butter on the egg, and close the griddle. In about the time it takes to make toast you have a fried egg that looks like a waffle. If you want to be gourmet, stir mayo into the egg before you fry it.