Mix ground beef with salt and pepper in a large bowl and form into 4 round patties. Set aside.
Toss sweet potato wedges with olive oil, salt, pepper in a large bowl.
Turn on grill (medium-high heat if using gas).
Lay the sweet potato wedges on first and allow to cook for about 5 minutes on each side.
While sweet potato fries are cooking, you can grill the avocado. Be sure to brush it with some olive oil before adding to the grill to prevent sticking. Sear for about 1-2 minutes or until it appears slightly charred. Remove from grill and set aside.
When potatoes are almost done, add on the burger patties. Cook for about 3 minutes on each side (for medium). Add slices of cheese towards the end to allow to melt.
Add a spoonful of mayo and/or ketchup. Place cheeseburger on top. Add pickle, tomato, and slice of grilled avocado. Top with additional leaf of lettuce and serve with sweet potato fries!