I have found several good recipes on Madhuram’s Eggless Cooking blog.  Its blueberry muffin recipe has a great tartness to it from the lemon zest and the lemon extract.  I use apple cider vinegar and fresh-squeezed lemon juice, and soy milk for the milk.  I’ve made the recipe with both fresh and frozen blueberries, and both are delicious.  I have found it best to refrigerate these muffins after the first day to keep them fresh.  They won’t last long on the counter…because they’re so delicious and because they have no preservatives.  Enjoy!