Preheat oven to 350˚ F. Line 2 muffin pans with 16 muffin papers.
In a large bowl, whisk together flour, flaxseed meal, ground cinnamon, nutmeg, baking soda, baking powder, and salt.
In a medium bowl, mash bananas very well. Stir in oil, maple syrup, vanilla, lemon juice, and water or milk until well mixed.
Add the flour mixture to the wet ingredients and mix until well combined. Fold in raisins, if using.
Fill the muffin tins to the rim with batter. Bake in the center of the oven for 20-23 minutes, or until golden brown on top. Cool completely before serving (these stick to the muffin papers if you don’t let them cool enough). Enjoy!