Preheat your grill to med/med high heat. Put ground beef in a large mixing bowl & add black pepper, 1 tsp sea salt, and zest of one lemon
Mix well and then form into thin patties all the same size
In another mixing bowl combine avocados, sun dried tomatoes, lemon juice, and the remaining teaspoon of sea salt.
Mash the avocado and mix ingredients well to get as smooth as you like
Place avocado mixture on top of the bottom of half of the burgers, leaving room to seal the burgers
Put the other patty over the top of the mixture & pinch the edges of your burgers together to seal all the way around
Grill to your liking, 6-8 minutes each side. Ensuring to cook evenly on both sides.
While grilling, drizzle the burgers with bacon grease if desired (it adds amazing flavor)
When done grilling, allow your burgers to rest for 10 minutes and then serve. Top remaining avocado mix & Enjoy!