Preheat oven to 350°. Line a 13x9-in. baking pan with parchment, letting ends extend up sides., In a large bowl, mix flour, brown sugar and salt; stir in 1 cup melted butter. Press onto bottom of prepared pan. Bake until light brown, 12-15 minutes. Cool 10 minutes on a wire rack. Reduce oven setting to 325°., In a large bowl, whisk the first 7 filling ingredients until blended; stir in 3 cups coconut. Pour over crust; sprinkle with remaining coconut. Bake until light golden brown, 25-30 minutes. Cool in pan on a wire rack. Lifting with parchment, remove from pan. Cut into bars.