Slice the pound cake loaf into 1/2-inch slices. With a 3-inch round cookie cutter, cut pound cake into 6 individual portions and place on a cookie sheet.
Place a large scoop of vanilla ice cream on top of each round cake. Freeze cake and ice cream until very hard, at least 1 hour.
While the ice cream freezes, make your meringue:
Preheat the oven to broil and place a rack 8 inches from the top of the oven.
In an electric mixer with the whip attachment, on medium speed, beat together the egg whites and cream of tartar to soft peaks. Continue to beat and add the sugar, 1 tablespoon at a time. Whip until meringue has reached stiff peaks. Place meringue in a pastry bag fitted with a large star tip.
Remove the ice cream from the freezer. Quickly pipe the meringue evenly over the ice cream, covering completely.
Place in the broiler and broil just until tops are browned, about 2 minutes. Remove from the oven and serve immediately.
Preheat oven to 350 degrees F.
Brush the inside of 2 loaf pans (9 by 5 by 3-inch) with melted butter. Line the bottoms of the pans with parchment paper and brush again with butter. Reserve.
Using a mixer fitted with the whip attachment, beat the butter and vanilla extract until creamy, about 5 minutes. Add the sugar, 1/4 cup at a time and continue to beat until light and fluffy, about 10 to 12 minutes.
Add the eggs, 1 at a time, making sure each egg is completely incorporated before adding the next one. Lower the speed to stir and add the flour and salt. Mix until well blended. Pour half of the batter into each prepared loaf pan.
Bake the cakes for about 1 hour, until the top is golden brown and a bamboo skewer inserted in the center comes out clean. Transfer pans to a rack and cool for 10 minutes. Then, remove cakes from the pan and allow to cool further on the rack. Serve slightly warm or use as needed.
Storebought pound cake can be used