In order to reduce the largest Contentful paint time, you should consider optimizing your server and use signed exchanges (SXGs). Optimizing your server will ensure that it is running at peak performance which may help with slow response times. Signed exchange guarantees are very important because they prevent a potential attack on the system by an unknown third party who might be able to steal or modify messages between two parties without detection thus enabling them access through this vulnerability in SSL/TLS protocol.