1 red pepper 
1½ pounds ground beef
1 teaspoon salt
1½ teaspoons black pepper
1 tablespoon Worcestershire sauce
4 pats butter
1/3 cup crumbled feta cheese
6 pitted, sliced Kalamata olives
4 gluten-free hamburger rolls, toasted

1. To make the peppers, cut open and remove the seeds from one red pepper. Cut the pepper into four quarters.
2. Heat oven broiler over high and then place pepper under broiler; let sit for 3 to 4 minutes, or until majority of the skin is charred and bubbling.
3. Carefully remove from under the broiler and place the quarters in a paper bag. Fold over the top and allow to steam for 15 to 20 minutes, or until cool enough to be handled. Remove any remaining skin.
4. To make the burgers, preheat the grill to high heat.
5. Combine the ground beef, pepper, salt, and Worcestershire sauce in a mixing bowl. Fold gently to spread out seasonings.
6. Separate into 4 patties, forming patty around the pat of butter. Indent the middle using your thumb or a spoon.
7. Place patties on a hot grill. Let sit for about 4 minutes and then turn; cook for another 4 or 5 minutes, or until internal temperature reaches 160 degrees. 
8. Let cooked patty sit for 5 minutes. Assemble toasted hamburger rolls. Place roasted red pepper on one bun half and cooked patty on another. Place feta cheese and olives on top of the patty and enjoy.