In a bowl, toss the shrimp with Cajun seasoning, olive oil, salt, and pepper until well coated.
In a large skillet over medium-high heat, add the shrimp and cook for 2-3 minutes on each side until they turn pink and cooked through. Remove the shrimp from the skillet and set aside.
In the same skillet, add sliced bell peppers and onion. Sauté for about 5 minutes until softened and slightly caramelized.
Warm the corn tortillas on a dry skillet or grill for about 30 seconds on each side until pliable.
Assemble the tacos by placing a layer of sautéed veggies on each tortilla, followed by a few shrimp, then top with sliced avocado, shredded cabbage, and a drizzle of sour cream or Greek yogurt mixed with lime juice.
Garnish with fresh cilantro and a squeeze of extra lime juice on top.