How to Make It
In a medium pot of boiling salted water, cook the green beans until just tender, about 4 minutes. Drain and rinse under cold water; pat the beans dry.
In a blender, combine the red wine vinegar with the garlic clove, shallot, mustard, oregano, thyme and basil and puree until smooth. With the machine on, slowly add the olive oil. Season the vinaigrette with salt and pepper.
In a large bowl, combine the blanched green beans, tomato halves, sliced onion and crumbled feta cheese. Toss with the vinaigrette and serve the salad immediately.