In a small bowl, combine the coffee rub seasoning mix ingredients and set aside.
In a large bowl, combine the mince with the salt and pepper. Mix well with your hands then divide into 4 equal patties. Rub the coffee seasoning mix over both sides of each burger.
Heat a large frying pan over a medium high heat then add a small knob of butter and toast the buns (sliced side down). Remove from pan to cool.
Add 1 tablespoon of butter to the pan and add the patties. Cook for about 4-5 minutes per side, or until the burgers are cooked to your liking.
Layer the BBQ sauce, lettuce, burger patty, and cheese inside the toasted bun to serve.