Tap water with TSP powder from the paint dept. at Home Depot and citric acid from bulk barn or Lemi-Shine, plus a dish washing rinse aid like Finish. Sometime I’ll add a touch of Calgon to soften the tap water.
I sometime use Hornady One Shot brass cleaner but only as a final “shine up” and I save that mix to a jug for another few uses because it’s quite expensive.
I do both US cleaning plus some time in the tumbler with SS pins, depends how clean the inside of the cases are from time in the US cleaner. I shoot mostly BP and the cases are fouled with a greasy waxy film plus the carbon.
I always deprime and clean the primer pockets first as this shortens the time spent in the machines.