Stir the brown sugar, sage, salt, basil, black pepper, onion powder, marjoram, and red pepper flakes together in a small bowl. Place the ground beef in a large bowl; mix the spice blend into the ground beef with your hands until evenly integrated. Refrigerate for 24 hours to let the flavors blend.
Divide the ground beef mixture into 8 patties.
Place a large skillet over medium heat; cook the patties in the skillet until firm, hot, and cooked in the center, 5 to 7 minutes per side. An instant-read thermometer inserted into the center should read 160 degrees F (70 degrees C).
