Recipes: Grilled summer squash and red onion with feta

Preparation:    Preparation time: 20 mins Cooking time: 20 mins Serving: 4 Ingredients: 1/2 cup plus 3 Tbsp. extra-virgin olive oil, plus more for grill 1 garlic clove, finely grated 1/4 cup white wine vinegar 4 medium summer squash and/or zucchini, cut lengthwise 1/4" thick 1 medium red onion, cut through root end...