Taylor Swift Slices Thumb in Cooking Accident ... Bad Kitchen Blood

Taylor Swift experienced a slice of life Saturday ... in the kitchen.

She cut her thumb open while cooking, then bandaged it up for her concert later that night in Texas.

Taylor tweeted, "Band aids don't fix kitchen knife related injuries" ... of course an oblique reference to "Bad Blood."

Taylor was unhampered by the injury ... easily manipulating the neck of her guitar during the concert.