Preheat oven to 325F. Lightly grease and flour a large cookie sheet or line with parchment paper; set aside. In a medium mixing bowl stir together coconut, sugar, flour, and salt. Using a wooden spoon, stir in egg whites and vanilla extract.
Drop coconut mixture by rounded teaspoons 2 inches apart onto the prepared cookie sheet. Bake in the preheated oven for 20 to 25 minutes or until edges are golden brown. Transfer to a wire rack and let cool. If desired, in a heavy 1-quart saucepan heat and stir chocolate and shortening over low heat until melted and smooth. Dip half of of each cookie in melted chocolate or drizzle melted chocolate over cookies. Place cookies on parchment or waxed paper and let stand until set. Makes about 30 cookies.