In 2-quart saucepan, cook 1/2 cup heavy whipping cream, 1/2 cup sugar and 2 egg yolks over medium heat 3 to 5 minutes, stirring frequently with heatproof spatula, until thickened and mixture coats back of spatula. Immediately pour into bowl of coconut/pecan mixture. Stir until butter is melted. Let cool to room temperature, about 1 hour. Mixture will thicken into icing as it cools.