(no porn, you'll have to look for that elsewhere) / in no particular order / ✔ = completed or one-shot

AO3

• A Very Sweet Heart by Daenarii / A Not So Sweet Heart by PhysicsIsLife - ongoing / 6 chapters each - basically 2 fics in one, written from 2 different POVs (one from Hugh's, the other from Paul's) / rating: T / how they met
• A Hundred Sunrises by nerdqueenenterprise - ongoing / 11 chapters / rating: M / AU - war on an alien planet, android!Paul / also has Michael/Tilly
• Incredible Tales of Scientific Wonder by RachelClark - ongoing / a series with currently 2 fics, one chapter each / rating: G / AU - working for NASA in the 1950s / also has Michael/Philippa
• head-heart malfunction by asweallfallfromgrace - ongoing / 6 chapters / rating: T / how they met
• ✔ A History of Mushrooms in Medicine by thericketandoo - completed / 6 chapters / rating: T / life snippets
• ✔ Loving Someone by sherlck - completed / 9 chapters / rating: G / how they met, AU-ish
• ✔ Remembering to Eat by 30MinuteLoop - completed / 3 chapters / rating: T / canon fill-in, spoilers for 1x10-1x14
• Bridging the Distance by thewatch - ongoing / 2 chapters / rating: G / how they met, AU-ish
• ✔ Lieutenant Stamets' Serious Medical Condition Which Is Very Serious by nerdqueenenterprise - one-shot / rating: G / life snippet-ish
• ✔ Because We're Here by letsstartagain - completed / 19 chapters / rating: T / how they met, life snippets, spoilers for 1x09
• ✔ The Karaoke Maru by misereremolly - one-shot / rating: T / how they met
• ✔ sleep inertia by gaysinspace - one-shot / rating: T / life snippet

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• untitled by shroom-boi - unfinished / (guessed rating: G) / speculation about things to come in S2, spoilers for S1
• ✔ untitled by shroom-boi - one-shot / (guessed rating: T) / life snippet
• ✔ untitled by shroom-boi - one-shot(?) / (guessed rating: T/M? I'm bad at this) / life snippet

These are my top favourites at this point, though there are a lot more that I also enjoyed, so you should definitely also go searching for more on your own! The completed ones are marked for easy recognition in case you don't like unfinished business. But I'd still highly recommend all the ongoing fics on this list, because I absolutely love every single one and I'm desperately waiting daily for each one of them to update again. Also I'd just like to note that I've read most, if not all, of these more than once (because I'm in that deep).