Prosciutto, Watercress, And Fontina Toasties

Preheat oven to 350u00b0F. Bake prosciutto on a parchment-lined baking sheet until it darkens and shrinks slightly, 6-8 minutes. Let cool (meat will crisp as it cools).

Top 4 slices of bread with half of cheese, prosciutto (breaking to fit), watercress, then remaining cheese (it will bind as it melts) and bread; butter tops.

Heat a large skillet over medium heat. Working in 2 batches, cook sandwiches, butter side down, pressing firmly, until bottom is golden brown. Butter tops, turn, and cook until golden brown and cheese is melted, about 4 minutes. Transfer to a wire rack; let cool slightly. Remove crusts and cut each sandwich into 4 triangles.