How do you record founders stock from an accounting perspective on your books? Does this count as an expense?

Question

one side of the entry would be equity but what is the other half

Answer 1

Not an expense- will be a capital account, common stock, paid-in-capital, etc.

Answer 2

You're correct that the credit would be equity.

The debit would be an asset - whatever the founder contributed at startup to get stock.  Most commonly cash.  Though it also could be fixed assets if he brought equipment into the business, stock in another company, etc.