You can easily turn your Pumpkin Spice Coffee Cake into a treat by making a few adjustments. Instead of using all-purpose flour use a gluten-free flour blend that can be substituted in a 1:1 ratio. Look for a blend that contains xanthan gum, which helps copy the binding properties of gluten and guarantees your cake keeps its texture. For the streusel topping consider using gluten-free graham crackers or almond meal to add a nutty crunch that complements the pumpkin flavor perfectly. Don't forget to check that your baking powder and baking soda are also gluten-free.