I don't ever really measure, but essentially, here's what I did:
1 cup of whole wheat flour (though next time I'd use less)
2 tbsp. cocoa powder (I recommend special dark - though being that my sister works at Mars, I can't condone Hershey's without a guilty conscience - you, on the other hand, feel free to use it.
About 1/2 cup Greek yogurt, I used my current obsession: Fage Greek yogurt
1 tsp. baking powder
About a tbsp. of almond milk
1 large banana, mashed
Optional: peanut butter for spreading on top (not optional for me)
With the yogurt and almond milk, I really just used enough to make sure it was in dough form and that the dry ingredients were no longer dry. And voila you have pancakes with the two greatest ingredients (chocolate and peanut butter, obviously).