To make this Moist Pineapple Cake gluten-free. Just use a gluten-free flour mix instead of all-purpose flour. Choose a mix. That replaces regular flour directly. Like those from Bob's Red Mill or King Arthur Flour. If the batter seems a bit thick. Add a little extra pineapple juice. Or a spoonful of Greek yogurt. To keep the cake nice and moist. This way, everyone can enjoy this delicious cake. No gluten needed!