Lemon Curd

• 4 egg whites
• 1 frosting (fluffy white)
• 1/4 bottled lemon curd
• 500 gr sugar
• 325 gr unsifted cake flour
• 240 ml milk
• 180 ml water (cold)
• 160 gr unsweetened coconut (shredded)
• 110 gr butter
• 20 gr powdered egg whites