Let pie thaw at room temperature for 30 to 45 minutes.
Preheat oven to 350 degrees. In a small saucepan, melt the stick of butter over medium heat. Add 1/2 cup brown sugar, 1 1/2 teaspoons cinnamon, allspice, cloves and lemon juice. Stir until well blended and sugar is melted, about 3 minutes. Make an X in the center of the top crust of the pie and fold back the crust.
Pour the butter mixture evenly into the pie and then replace the crust.
Leave 4 vent holes, sealing the rest of the pastry. Bake for 30 minutes.
Remove from the oven and set aside. Reduce heat to 325 degrees.
Grate frozen butter into a medium-sized bowl. Toss the grated butter with flour, remaining sugars, remaining cinnamon and walnuts.
Carefully wrap an aluminum foil band around the edge of the pie creating a lip to hold topping. Sprinkle topping evenly over pie.
Bake for 30 to 40 minutes. Let rest for 10 minutes then serve with ice cream, if desired.