Ben Affleck -- Support the Congo ... And BTW, Their Chocolate is Awesome! (VIDEO)

Ben Affleck loves the people of the Congo, and really loves their coffee and chocolates.

Our photog Colin got Ben coming out of a Senate hearing where he testified about his Eastern Congo Initiative, which helps people in the region.

Ben mused about the beans and the bars ... and acknowledged Senator Patrick Leahy who has a cameo in the upcoming "Batman v Superman: Dawn of Justice."

In the hearing, Ben said to Leahy, "I would be remiss if I did not acknowledge my co-star in Batman. The role is marginally smaller than; mine, but I understand you are quite good."