Been hunting for cream/vanilla fics myself lately! The best places really depend on if you're looking for the classic fluffy stuff or something with a darker twist. Archive of Our Own is my main hub—the tags are super specific, so you can filter by 'Fluff', 'Established Relationship', or even 'Alternate Universe - Coffee Shop' to get that sweet, low-conflict vibe. I've found some real gems there where the dynamic is just pure comfort.
Tumblr still has a strong community for softer pairings too, especially if the ship started in a slice-of-life anime or a chill game. People reblog threads and headcanons constantly, and sometimes those evolve into full one-shots. The tagging system is chaotic but if you dig, it's worth it. For more niche or older fandoms, I've had luck on Fanfiction.net using the 'Romance' filter and sorting by favorites—some authors there have been writing gentle, vanilla-centric stories for years, way before 'wholesome' became a mainstream tag.
Honestly, the term itself can be tricky because 'vanilla' means something totally different on certain NSFW sites, which is a whole other can of worms. On AO3, sticking to 'Fluff' and 'Soft' tags usually gets you there without accidentally stumbling into unrelated kink material.