Place 4 bread slices on a surface and spread mayonnaise on one side.
Mix spinach and chopped eggs with mayonnaise and spread on bread.
Cover with another bread slice, previously spread with mayonnaise on both sides.
Cover with tomato slices and season with salt and pepper. Arrange cheese slices on top and cover with another bread slice with mayonnaise on the bottom part.
Press and cut sandwich diagonally in two.