Preheat oven to 375 F. In large bowl, using a wire whisk, whisk together eggs, pumpkin, evaporated milk, 3/4 C. brown sugar and pumpkin pie spice. Place frozen pie crust on preheated baking sheet. Pour filling into crust. Bake 40 minutes. In small bowl, combine remaining 1/4 C. sugar, pecans and melted butter. Crumble over top of partially baked pie. Bake an additional 30 minutes, or until tested done.