This is basically the pear-fect fall dessert.
In saucepan, whisk cream, sugar, 4 tbsp. butter, Scotch, and 1/2 tsp. salt over low until sugar dissolves. Simmer until thickened, about 5 minutes. On foil-lined baking sheet, arrange pears, cut-side up. Brush with 1 tbsp. melted butter. Broil until browned in spots, about 5 minutes. Drizzle pears with butterscotch sauce. Top with pistachios.