Crazy Cups Hot Chocolate Variety Pack maybe this? I think Two Rivers has several kcup companies under it, and I always forget which ones are included. And I've noticed crazy cups rotates their variety pack flavors a lot. So maybe either the dulce de leche in this pack is what you had, or there was a butterscotch one previously. I did see another coffee variety pack that had Friendly's Butterscotch flavored.
And it's not a kcup as far as I know, but Land O Lakes has a really good butterscotch hot chocolate packet.