Halve each avocado and remove the pit. Use a knife to score the avocado down to the skin, 3-4 times across the width and 3-4 times down the length to make ½ cubes. Use a spoon to scoop the meat out from the skin, and place the cubes in a large bowl.
Immediately squeeze the juice of half a lemon over the top and gently toss to coat. This well help the avocados not turn brown as quickly.
Slice the cucumber in half lengthwise, rotate 90° and slice again, making 4 long pieces. Cut the pieces into ½ inch cubes. Add to the avocado
Also add in halved tomatoes, feta, red onions and cilantro. Season with salt and pepper to taste.
Serve immediately with pita, tortilla chips, or plain. If desired, allow to chill for an hour and serve cold.
