I love putting avocado on sandwiches and for this one it combined very well with the spicy arugula and sweet tomato. Take a look:
Ingredients (makes 2 sandwiches):
4 slices of bread, toasted
Few slices of tomato
2 handfuls of arugula
Salt and pepper
In a bowl, mash the avocado with salt and black pepper. Spread mashed avocado on a slice of bread, add a handful of arugula, arrange tomato slices and top with other slice of bread. Cut sandwich in the middle. Serve and enjoy!