Butter your bread slices. Place one slice of bread butter-side-down on a plate or baking sheet. Drizzle the bread with BBQ sauce. Add a layer of cheese. Add the bacon, more BBQ sauce and another layer of cheese. Place the second slice of bread butter-side-up on top.
GRILL your sandwich until golden brown on both sides. You want the grill kind of low so you don't torch the bread (you can also do this on the stove in a pan, of course). Close the lid on the grill so your cheese melts. Flip and toast the other side.