Step 1Combine the shallots and the vinegar in a small bowl and set aside at least 1 hour. Combine the garlic and one-fourth cup of the oil in another small bowl and set aside at least 30 minutes. In a small bowl beat together the goat cheese and chives.
Step 2Heat the oven to 400 degrees. Slice the baguette at a sharp angle to create 8 long, three-fourths-inch thick spears of bread. Strain the garlic from the olive oil and brush the bread on both sides with the oil. Discard the garlic or save for another use. Place bread on a baking sheet and bake until golden, 25 to 30 minutes.
Step 3Put the tomatoes in a wide bowl and season well with salt and pepper. Strain the vinegar from the shallots into a small bowl and then beat in the remaining one-fourth cup of oil. Pour this over the tomatoes and toss gently to coat the slices without breaking them.
Step 4Rap each toasted baguette slice rather sharply in about the middle with the back of a chef's knife to break it into a couple of large, rough pieces. Spread each piece with the goat cheese mixture.
Step 5Arrange the dressed tomatoes in a wide serving bowl or on plates, being careful to mix colors and sizes. Carefully separate the shallot slices into individual rings and scatter them over top. Arrange the bread spears around the outside and serve.