Egg Salad Sandwich

8 eggs, hard-boiled, cooled, and shelled
½ cup finely chopped red onion
3 garlic cloves, minced
1 ½ teaspoons coarse salt
1 teaspoon coarsely ground black pepper
1 cup Homemade Mayonnaise
¼ cup fresh basil, cut into strips
2 cups watercress, stemmed

Separate the yolks from the whites of the egg and crumble into a medium bowl. Lay the whites on a cutting board and finely chop. Add to the yolks. Stir in the onion, garlic, salt, pepper, and mayonnaise. Spread onto 4 slices of bread, sprinkle with basil, cover with watercress, and top with the remaining bread slices. Cut in half and serve.