Sure, we don't have Mario Kart on PC (unless you emulate it). But we do have the next best thing, and I don't mean Sonic & All-Stars Racing Transformed, although actually it does rule. I'm talking about Halo Kart, a mod by InfernoPlus that was released last year but is now in the public eye again thanks to a post on the Halo subreddit.
Halo Kart takes five tracks from the Nintendo 64 version of Mario Kart, tweaks them a little, and then lets Spartans squatting on top of miniature Warthogs loose to race around them. It even has power-ups, although of course they're Halo-themed rather than blue shells and banana peels.
To play Halo Kart you'll need Halo Custom Edition, the free add-on for the original PC release of Halo: Combat Evolved, rather the Master Chief Collection. Patch it up to 1.10 and follow the instructions on InfernoPlus's Patreon to get the mod and get it running. Prepare for Halo Kart to be buggy as heck, because of course it is. Those Halo Arrays were designed to wipe out all life in the galaxy, not be raced across on kart-sized Pumas.