How do I tell my DNS server to update it's cache?

When I'm on my corporate network, and a new AWS FQDN is created, it takes 15 minutes before the DNS record is resolvable.

But from outside the network, it's almost immediate. This tells me that:

A. The AWS record is properly updating in top-level DNS servers B. Our internal DNS server is not syncing/caching with it's nearest DNS server (ISP, google, etc..) for ~15 mins.

I think it has to do with tweaking the TTL for externally resolvable FQDNs but I could be totally wrong. Hence the reason I'm posting here. Can any pros here tell me how I can tell my internal DNS server (Windows) to check the records of the next DNS server more quickly so that we can resolve the AWS domains sooner?