Grapefruit Custard Pie {Gluten-Free}

Ingredients

• almost-fully-baked 9" gluten-free pie shell, hot
• tablespoons sweet white rice flour )
• organic blonde cane sugar )
• teaspoon salt
• large eggs
• tablespoons melted butter )
• strained ruby/pink grapefruit juice )
• tablespoons strained blood orange juice )
• heavy cream
• tablespoons St. Germain Elderflower Liqueur
• teaspoons finely grated grapefruit zest )