To make this Nutrigrain Bar Recipe gluten free, replace the whole wheat flour with a gluten-free 1:1 baking flour blend. Use certified gluten-free rolled oats, as oats may be cross-contaminated with wheat during processing. Verify that the vanilla yogurt, maple syrup, vanilla extract, and berry jam are labeled gluten free. Use clean utensils, bowls, rolling surfaces, and baking sheets to prevent cross-contact with gluten-containing ingredients.