Coconut Penuche

2 cups firmly packed brown sugar
1 cup granulated sugar
1/2 teaspoon salt
1 1/3 cups milk
1/4 cup butter or margarine
2 teaspoons vanilla extract
1 1/3 cups sweetened flaked coconut

Line an 8-inch square baking pan with lightly buttered wax paper or aluminum foil. Set aside.

Combine sugars, salt and milk in large saucepan. Cook over medium heat, stirring constantly, until sugar dissolves and mixture boils. Continue cooking until a small amount of mixture forms a soft ball in cold water (or to a temperature of 236 degrees F / 110 degrees C), stirring frequently after mixture begins to thicken. Remove from heat. Add butter and vanilla extract. Cool until lukewarm (110 degrees F / 45 degrees C) without stirring. Add coconut. Beat with heavy wooden spoon until mixture loses its gloss. Turn out at once into prepared pan. Allow to cool at room temperature. Cut into squares.