Prepare graham cracker crust by mixing 1 1/2 cups graham cracker crumbs, 3 tablespoons sugar and 1/3 cup plus 1 teaspoon melted butter together. Press into bottom of a 9x13 pan. Bake at 350 degrees for 8 minutes.
Pour 3 cans of sweetened condensed milk into mixing bowl. Add 1/2 cup freshly squeezed lemon juice, drained crushed pineapple, 2 teaspoons vanilla, 1 cup chopped pecans and 1 of the 8 oz containers of extra creamy cool whip. Mix well and pour over prepared graham cracker crust. Place in refrigerator for 2-3 hours or overnight to set. Spread remaining container over top before serving. Enjoy!