Sources on US Large-Scale Birthday Cake Production for Documentary

Private Label Bakeries Documentary Request Hello everyone! I'm a documentary filmmaker working on a piece about the history of American birthday celebrations. One aspect of the film we're hoping to document is the production of birthday/celebration cakes on a massive scale in the modern age. I'm reaching out here to se if anyone has any advice or thoughts on companies or locations I may be able to reach out to that produce cakes like this on a large scale. Any help, suggestions, or contacts are very very helpful as my research has resulted in a lot of dead ends. Please feel free to DM me or reply below. Thank you all so much!