Wash your english cucumber and tomatoes. Halve the cherry tomatoes and slice the cucumbers into half moons. I link slicing my cucumbers slightly thinner, but feel free to keep this salad nice and chunky. Also, slice your red onions and add them to the bowl.
In a small bowl or liquid measuring cup, add grapeseed oil, white wine vinegar, garlic powder, onion powder, sugar, salt and pepper. Whisk vigorously until emulsified.
Pour the dressing over the veggies and toss to coat. You can serve immediately, or cover with plastic wrap and refrigerate about an hour to marinate the veggies so they really absorb the flavors from the dressing. Serve!