Broil shrimp 6-8 minutes. Cool. Dice into bite-size pieces.
Heat olive oil in skillet. Add garlic and onion and cook until translucent (5 mins). Add cabbage, carrot, and spinach. Cook 2 mins. Add shrimp and toss. For sauce melt butter. whisk in flour and gradually whisk chicken stock. Stir in sour cream. Assemble tortillas. Pour sauce over the top.