To make this Lebkuchen German Cookies Recipe gluten free, substitute the all-purpose flour with a high-quality gluten-free all-purpose flour blend designed for baking. Ensure that the baking powder, spices, and almond extract are labeled gluten free, as some brands may contain additives or be processed in facilities with gluten. The remaining ingredients are naturally gluten free. Baking times and texture should remain similar when using a suitable gluten-free flour blend.