Let's jump right in. Start with any kind of local, fresh tomato. Heirloom, dry farm, plum, cherry... anything fresh works. Just don't use a supermarket baseball that is hard and mealy.
Step 1: Cukes
Cut up some nice cukes. Organic, local ones are best, but I'm more forgiving of supermarket cukes that tomatoes, if you peel off the skin.
Step 2: Onion Time
Fresh red onion, yah
Step 4: Feta Time
feta is the betta
Step 5: Mix With Oil, Vinegar, and Serve