Heat 1 tablespoon oil in a large pan over medium heat and add shrimp in a single layer. Sprinkle Cajun seasoning and squeeze lemon juice over top. Sauté until cooked through (they should be pink and opaque) and then transfer to a plate, about 5 minutes.
To the same pan, add the remaining 1 tablespoon of oil and the vegetables. Sauté until soft and lightly caramelized, about 10 minutes.
Turn off the heat and add the shrimp back to the pan.
Divide shrimp and vegetables into warm tortillas and serve with desired toppings.
Notes
Cajun Seasoning SubstituteIn place of the Cajun seasoning, you can use the following combination:¾ teaspoon paprika, ½ teaspoon fine sea salt, ½ teaspoon black pepper, ½ teaspoon garlic powder, ¼ teaspoon onion powder, ¼ teaspoon dried oregano, ¼ teaspoon cayenne pepper, pinch dried thymeLeftoversStore leftover shrimp and vegetables in an airtight container in the refrigerator for up to 3 days. Reheat and assemble when ready to eat.*Nutrition includes corn tortillas and fajita vegetables but does not include toppings.