Add frozen bananas, almond milk, peanut butter, cocoa powder, dates, and chia seeds to a blender. Start with 1/3 cup of milk and blend on high until smooth. You may need to add additional milk (up to 1/2 cup), depending on how large your bananas are, and how powerful your blender is.
When ingredients are smooth and desired thickness is reached, pour or scoop out smoothie into a bowl. Top with chopped peanuts, additional chia seeds, and chocolate chips.