Beat egg whites and cream of tartar at high speed with an electric mixer until foamy. Gradually add sugar, beating until stiff peaks form. Fold in 3/4 cup nuts.
Drop egg white mixture into 6 mounds on a large baking sheet lined with parchment paper. Make an indentation, using the back of a spoon, into the center of each meringue to form a 5-inch nest.
Bake at 225 for 1 hour. Turn oven off, and let stand in closed oven 8 hours.
Spoon Pineapple Filling evenly into center of each nest.
