1. Preheat grill to medium high heat, about 400°F. For a charcoal grill, arrange for direct heat.
2. If using multiple varieties of beef, blend well in a bowl by hand. Form into four patties, using a burger press, if available.
3. Add rub ingredients to a bowl and mix together.
4. Rub both sides of each patty well with coffee rub. Try to avoid contaminating any remaining rub with raw beef, so that it can be saved for future use.
5. If grill grate is not pre-oiled, spray with grilling spray to avoid sticking.
6. Cut the hamburger buns in half if not pre-sliced and brush the cut sides with oil.
7. Place patties on grill and close lid. Grill for approximately 4 minutes per side.
8. For the last minute of grilling, add Castelo® Burger Blue cheese slices on top of patties, close lid again and allow to melt over tops and sides of patties.
9. Remove patties from heat and allow to rest for 2 to 3 minutes.
10. Place buns cut side down on the grill for about 30 seconds to a minute, until cut edges are slightly browed or charred.
11. Remove buns from heat and spread condiments of your choice on cut side. On bottom bun, layer green leaf lettuce, tomato, burger, bacon, and top bun.