How to get baby to sleep longer stretches of sleep at night in bassinet?

LO is 7 weeks old and has a strong feed to sleep association since birth. She will only fall asleep while breastfeeding and we will need to wait until she is in deep sleep before we can set her down in her bassinet. Even then, she wakes up within 30-40 minutes grunting and crying from gas and is unable to settle herself back to sleep. She manages to sleep like 4 hours on our chest though but we are trying to be consistent with the bassinet in hopes that it will stick one day. So we are picking her up, comfort feedingg her back to sleep on our chest, then putting her down in her bassinet once she gets into deep sleep again then rinse and repeat.

I am wondering if maybe anything will be different if we practice transitioning her to the bassinet in a "drowsy but awake" state but not sure where to start. Exhausted and just trying to get more than 30-40 minute stretches of sleep at night before waking up and starting all over again. Any advice is appreciated!