All at once.
That would be my answer for any amount of money.
If it were an amount that allowed me to FIRE, then I'd put 75% in VTSAX and 25% in Bonds, and I'd start a 4% withdrawal.
If it were an amount that didn't allow me to FIRE (Like 100k), then I'd just put 100% in VTSAX so it could grow as fast as possible.