Hottest thing I've ever ate was hot sauce made with concentrated Habenero extract which is way more heat than I can enjoy.
The hottest pepper in the world is the Carolina Reaper (~2m scovilles). Pure capsaicin, the thing in peppers that makes your mouth burn, is 15-16m scovilles.
If you want hotter than that you can try eating some Resiniferatoxin (RTX) from a cactus in Morocco. Idk if eating the plant actually burns but the RTX chemical found inside comes in at a cool 16billion scoville units.
