What is a certified car charger for an iPhone 12 mini?

This model is carried in Apple’s store and at 18W supports your phone’s fast charging capability.

mophie Dual (USB-C/USB-A) Car Charger

https://store.apple.com/xc/product/HN822ZM/A

as does this slightly less expensive

model:mophie USB-C Car Charger

https://store.apple.com/xc/product/HN7Z2ZM/A

if it has a connector that match your charging cable and does not output higher than 5volts and can supply a minimum of 0.5 amps then anything should work