This Easy Lemon Mousse is naturally gluten-free, as it contains no grains or flour-based ingredients. To ensure it remains safe for those with gluten sensitivities, verify that all ingredients—especially the mascarpone cheese and powdered sugar—are certified gluten-free and processed in a gluten-free facility. If serving with cookies or toppings, choose gluten-free shortbread or biscotti to complement the mousse.