Like someone already said, mix up your stroke speeds and depths. Sometimes you have to take it all the way out and suck some tiddies, toes, butthole, cootie cat, etc. Then put it back in and repeat previous steps.
Or you can power through the nut butt don’t cum til the last drop, pull out and let it drip out some, then put it back in. Depending on y’all level of freakiness, you can dab some on her lips or her butthole and stick your thumb in her butt while you proceed to stroke slooooooow.
Or you can give her a fantastic foreplay extravaganza whereas she is dripping wet or even busted a nut herself(I have a cool method of making a woman bust with only my fingers, gonna find the video), THEN you can start stroking her however you want because she already climaxed or is ready to climax. When a chick is ready to climax, you in are in complete control of the timing of it, use it to match up with your nut so that y’all can explode at the same time. After that y’all can chill a lil bit because y’all used kinetic nut energy.
Or just keep yourself healthy whereas you can nut back to back without stopping.