Pat shrimp dry with paper towels.
In one bowl, add buttermilk.
In another bowl, mix cornstarch, garlic powder, paprika, salt, and pepper.
In a small bowl, whisk together mayonnaise, sweet chili sauce, sriracha, honey, and lime juice.
Dip shrimp into buttermilk, then coat in the seasoned mixture.
Heat oil to 350°F in a deep pan.
Fry shrimp in batches for 2–3 minutes until golden and crispy.
Remove and place on paper towels.
Toss shrimp gently in the bang bang sauce.
Warm tortillas and assemble with cabbage, shrimp, and green onions.
Add cilantro and a squeeze of lime, then serve immediately.