To make these biscuits gluten-free, substitute the all-purpose flour with a 1:1 gluten-free baking flour blend that contains xanthan gum. Verify that all other ingredients, such as baking powder and sugars, are certified gluten-free to prevent cross-contamination. Due to the differences in gluten-free flour absorption, you may need to adjust the milk quantity slightly to achieve a soft but workable dough.