In a bowl, combine the mayonnaise, sour cream, minced garlic, cilantro and lime juice. Stir to combine well.

In another bowl, place some of the dressing on the coleslaw mix, and stir to combine well.

Heat the oil and butter in a skillet over medium high heat.

Add the shrimp to the skillet with the taco seasoning, and saute until cooked through.

Place a layer of the coleslaw mixture in the bottom of the tortillas, top with shrimp and garnish with the tomatoes, feta cheese and avocado. Drizzle with the remaining sauce mixture and serve.