Ingredients: 
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2 avocados, divided
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2 tsp. Worcestershire sauce
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1 tsp. garlic powder
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1 tsp. ground cumin
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3 tbsp. plus ½ cup mayonnaise
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4 tsp. Sriracha, divided
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1½ tsp. kosher salt, plus more
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½ medium red onion, divided
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1 lb. ground turkey
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4 tbsp. extra-virgin olive oil, divided, plus more for greasing
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3 cups very thinly sliced red cabbage (from ¼ medium head)
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2 tbsp. fresh lime juice, divided
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4 hamburger buns, toasted
Directions:
1. Mash half of 1 avocado with a fork in a medium bowl until smooth (reserve remaining half for topping burger). Add Worcestershire, garlic powder, cumin, 3 tbsp. mayonnaise, 2 tsp. sriracha, and 1½ tsp. salt. Grate half of the onion into the bowl. Mix with a fork to combine. Add turkey and mix thoroughly with clean hands until the mixture is homogeneous.
2.Drizzle 1 tbsp. oil on a large plate. Using oiled hands, form turkey mixture into 4 balls, place on a plate, and press down into patties 4–4½” across . Chill, uncovered, at least 10 minutes and up to 2 hours. If chilling for more than 2 hours, cover with plastic and chill up to 2 days.
3. Meanwhile, stir the remaining ½ cup mayonnaise and 2 tsp. Sriracha in a small bowl and season with a pinch of salt.
4. Thinly slice remaining onion and toss with cabbage in a medium bowl.
5. Heat 2 tbsp. oil in a large nonstick skillet over medium. One by one, carefully slide patties off plate into skillet. Cook until dark brown underneath, about 5 minutes. Turn and cook on the second side until burgers are fully cooked, about 5 minutes more. Transfer to a wire rack and let rest while you finish assembling.
6. Thinly slice remaining 1½ avocados. Add lime juice and the remaining 1 tbsp. oil to cabbage mixture and toss to combine; season with salt.
7. Divide Sriracha mayo among cut sides of buns, spreading to edges. Place patties on bottom buns, then shingle avocado slices over. Heap slaw over avocado.