Our apple pie was supplied through Arm and Hammer
Jay smartly brings together two images here — his desire for a “piece of the [economic] pie” and the cliche of something being “as American as apple pie”. In this case, Jay’s piece of the American dream came through his drug dealing. Baking soda is an active ingredient in crack cocaine
A far more subtle implication is that unethical business deals (drug dealing is commonly considered one) are nothing new and, like the apple pie mentioned at the line’s beginning, are a quintessential symbol of America.
To help improve the meaning of these lyrics, visit "Made in America" by Kanye West (Ft. Frank Ocean & Jay Z) Lyrics and leave a comment on the lyrics box