Trim baguette ends and slice off top and bottom so both sides are flat, then halve horizontally. Spread 1 T. butter on one side of each baguette piece. Layer 2 oz. cheese on the unbuttered side of one baguette half. Top cheese with ham, remaining cheese, and baguette half, buttered side up. Preheat griddle or large nonstick skillet over medium. Put the sandwich on the griddle, pressing it lightly with a spatula. Cook sandwich until golden on one side, about 3 minutes. Flip and grill until bread is toasted and cheese is melted. To serve, slice sandwich into 8 equal pieces.
Makes 8 servings.