Halve 2 eggplants lengthwise and rub the cut sides with 1 smashed garlic clove; brush with olive oil and sprinkle with salt. Grill until charred, 8 minutes per side. Let cool, then chop. Whisk 3 tablespoons plain yogurt, 2 tablespoons olive oil, 1 tablespoon white wine vinegar and 1 grated garlic clove; season with salt and pepper. Toss with the eggplant, 1 cup halved cherry tomatoes and 1/2 cup chopped mixed herbs.