Place the softened butter in a bowl and use a fork to mash it. Add the garlic and fresh basil and gently stir to combine. Place on a sheet of wax paper and roll up, twisting the ends to press the butter into a uniform shape. Refrigerate for 2 hours, or freeze for 15 minutes to firm back up.
Combine all the steak marinade ingredients in a zip close bag, then add the steaks. Make sure the steaks are covered in the marinade well. Allow the steaks to marinade for at least 15 minute, longer if possible. Let steaks sit at room temperature for at least 15 minutes prior to grilling.
Heat the grill to medium heat then add your marinated steaks. Discard any leftover marinade. Grill to your desired doneness. (I prefer a medium steak which is still pink in the middle).
Once the steaks are done, immediately add a tablespoon of the compound butter on top. Let it melt into the steaks, then enjoy!
The steak marinade will work for up to 4 steaks. If you need more, simply double the recipe!