Thaw and peel prawns.
In a small bowl, whisk together the olive oil, spices, garlic, and lime juice.
Pour marinade over the prawns and marinade for 5-20 minutes. Not longer or the acidity of the lime will cook the prawns.
Heat olive oil in a skillet over medium-high heat and cook the prawns for 2 minutes per side.
While the prawns cook, prepare the mango salsa. Or make it ahead of time, and store it in the fridge.
Toast the tortillas and assemble your tacos, starting with chopped green cabbage, blackened prawns, mango salsa, white onion, cilantro, Cotija cheese, and lime.
Serve and enjoy!