Chop all veggies. Toss the cucumbers, tomatoes, onions, in a bowl. Drizzle the olive oil and lemon juice over the salad and toss to coat.
Season with salt and pepper to serve.
It tastes even better if you can allow it to chill in the fridge for a couple hours first while the flavors meld. Some people also like to make this with about 1-2 tsp white vinegar mixed in to help the flavors pop!