AFTER you warm up with the BWF writing challenge https://bestwritingforum.com/index.php/topic,931.0.html , Consider entering your flash stories 500 - 1000 words for consideration at Flash Fiction Online http://flashfictiononline.com/main/submission-guidelines-flash-fiction/

Be sure to read their submission guidelines, and their "hard sells" page for tips on what they're not looking for.

They pay $60 per accepted story. Not bad!