To make the vinaigrette combine the garlic, Dijon, vinegar, salt, and black pepper in a medium size mixing bowl and whisk to combine. Slowly drizzle in the olive oil as you whisk until the mixture is completely emulsified. Adjust seasoning if needed. To make the Panzanella, combine all the ingredients in a large mixing bowl reserve half of the bread and half of the feta for garnish. Drizzle in the vinaigrette generously and toss the salad. Garnish with leftover feta and bread. Serve!