Place oil, vinegar, and minced garlic in small mixing bowl.
Zest the lemon into the same bowl.
Juice the lemon and add to bowl
Add sweetener and thoroughly mix. You can add more later once the salad is mixed.
Add the dressing to the salad and thoroughly mix so that the dressing covers all the ingredients. It shouldn't need more sweetener, but taste it to be sure. Besides, it's yummy.
Let the ingredients sit for at least five minutes so the flavors blend. If it'll be more than five minutes, refrigerate it. I don't recommend refrigeratoring it overnight, as the tomatoes and cucumbers will lose their liquid.