I assume then that you're just leasing space from the hospital and the physician bears all of the costs of the practice, correct? If that is the case, then yours is not considered a provider based practice. Your services should be billed just as if you were billing in a physician office practice, on a 1500 form under your own TIN and with place of service 11. The hospital would not bill any services on the UB-04.
'Incident to' would apply just as it would in an office setting - if your practice chooses to do that and the requirements are met, you could bill your mid-level services under the supervising provider's credentials. If you wish to bill that way, you can instruct the hospital coders to do it that way. These are your practice's claims and they are ultimately your practice's responsibility, so you should be auditing the hospital's coders to ensure they're doing it the way you want them to.