Slice the focaccia bread into two pieces. On one side, spread the mayo and on the other side spread the basil pesto.
On the bottom piece of focaccia, place the turkey slices in a single layer. Top with cheese, spinach, and more turkey slices.
Cover the bottom piece of focaccia with the top slice. Press down on the top of the sandwich firmly to secure all the ingredients inside. Cut the sandwich into small squares. Enjoy!