Preheat the oven to 350°F. Line 9-10 muffin cups with liners and spray the liners with nonstick cooking spray (I like coconut oil spray).
In a small to medium bowl, whisk together the oat flour, tapioca flour, ground flax seed, baking soda and salt.
In a separate large bowl, whisk together eggs, honey, vanilla, almond milk, coconut oil and lemon juice until smooth and well combined. Add dry ingredients to wet ingredients and stir until just combined.
At this point, add whatever mix ins you have on hand like chocolate chips, blueberries, strawberries, apples and cinnamon or more.
Use a large spoon to fill the prepared muffin liners all the way to the top, but not over the top. It should fill 9 to 10 muffin cups. Place a few extra blueberries on top of each one before baking. Bake in the preheated oven for 20-24 minutes or until a toothpick inserted comes out clean.
Transfer muffin tin to a wire cooling rack and allow to cool for 5-10 minutes then remove the muffins from the tin and allow to cool completely or serve warm.