Steps
1. In a bowl, combine the brewed coffee, minced garlic, soy sauce, brown sugar, Dijon mustard, black pepper, and salt.
2. Place the steak in a resealable plastic bag and pour the marinade over it.
3. Seal the bag and refrigerate for at least 2 hours or overnight.
4. Preheat the grill to medium-high heat.
5. Remove the steak from the marinade and discard the marinade.
6. Grill the steak for about 4-5 minutes per side for medium-rare or adjust the cooking time according to your preference.
7. Remove the steak from the grill and let it rest for a few minutes.
8. Slice the steak against the grain and serve.