Melt the coconut oil in a large skillet over medium heat. Add shrimp; cook for 5 minutes or until they start to turn pink.
Add next 5 ingredients (garlic through cumin); cook for 10 minutes or until shrimp are pink throughout and curled into a ācā shape. Stir in tomatoes.
In a large bowl, layer lettuce, shrimp mixture, avocado and onion; serve.