Cut tomatoes in half and remove core. Place in a large bowl with olive oil, garlic, basil and 1/2 tsp salt. Place cut side down on a baking sheet and bake in a preheated 400 degree oven for 40 minutes or until browned on top.
Once out of the oven, pinch off skins and discard.
In the meantime, steam green beans over boing water until tender but not mushy, about 5 minutes.
Place beans and tomatoes in a serving dish. Combine all vinaigrette ingredients and whisk until smooth. Add to beans and tomatoes and toss. Add Parmesan cheese and toss. Serve warm.