I use a generic usb-c charger that I bought at "5 Below" along with a 10ft usb-c to usb-c braided cable. For $16 total. ($8 each. I know it's called 5 Below, but they have an extended price section in tech. Up to $10-12).
On Ampere, I register 3650ma charge rates. Which is about 20-21 watts @ 5v. Which is interesting to me... Considering both the pixel and the charger are rated at 18w max.
The charger also has an automatic switch to 9v @ 2a, and 12v at 1.5a.
I can charge from 0 to 50% in about 25-30 minutes.
Granted it's no Ferrari by today's high end standards that can fully charge a 4500mah battery in 15 minutes. Lol
It's still not too shabby. And for the price, I don't think I could have done any better.