Chickpea Salad Sandwich

Name: Chickpea Salad Sandwich
Ingredients: 1 (15-ounce) can chickpeas , rinsed and drained; 2 ribs celery , diced; 2 tablespoons capers , rinsed and drained; 3 tablespoons mayonnaise; 2 tablespoons lemon juice; 1/2 teaspoon Dijon mustard; 1/8 teaspoon salt; 2 pinches black pepper; 4 slices sandwich bread; 1/2 avocado; 2 tablespoons roasted almonds , coarsely chopped; 2 to 4 tomato slices; Handful watercress or other greens, such as lettuce, arugula, or spinach