Step 1

To prepare fries: Preheat oven to 425 degrees F.

Step 2

Slice sweet potato into 1/4-inch-thick matchsticks. Place on a baking sheet, drizzle with oil, and toss to coat. Sprinkle with 1/8 tsp. salt. Bake, flipping halfway through, until tender and crisp-edged, 20 to 25 minutes.

Step 3

Meanwhile, prepare burgers: Using your hands, mix turkey, Cheddar, Worcestershire, garlic powder, pepper, and salt in a medium bowl. Shape into two 4-inch patties, about 3/4 inch thick.

Step 4

Brush oil over a medium nonstick or cast-iron skillet; set it over medium heat for 2 minutes. (Alternatively, to grill, see Tip.) Add the patties and cook for 2 minutes. Flip and cook for 2 more minutes. Cover the pan and continue to cook until the patties are lightly browned but still juicy (the juices should run clear, not pink), and an instant-read thermometer inserted in the center registers 165 degrees F, 2 to 4 minutes more.

Step 5

To assemble the burgers, top each patty with a slice of onion and tomato, and half the avocado slices. Carefully wrap each one in 2 to 3 lettuce leaves, wrapping as tightly as you can. Serve with the sweet potato fries.