Preheat oven to 375 degrees F (190 C) and lightly butter two small ramekins with non-dairy butter.
To make flax egg: In a liquid measuring cup, add flaxseed and water and set aside.
In a large bowl combine flour blend, brown sugar, baking soda, salt and whisk.
To the liquid measuring cup, add almond milk, vanilla, melted butter, flax egg and stir. Add to dry ingredients and stir until combined. If batter appears a bit too thin, add another Tbsp or so of flour. If batter appears to dry, add another Tbsp or more of almond milk.
Toss the blueberries in 1-2 Tbsp of the gluten-free flour blend so they don't settle to the bottom when baking (amount as original recipe is written // adjust if altering batch size). Then fold them in to combine.
Divide batter evenly into the two ramekins – about 1/2 to 3/4 full – and sprinkle with a few more blueberries. If using a standard muffin tin, it will likely make 3 or 4 (amount as original recipe is written).
Bake for 25-30 minutes or until the tops are golden brown and a toothpick or knife inserted comes out clean.
Let cool for a few minutes, then remove from ramekins and serve warm. A little vegan butter would make the perfect addition, but not necessary. Will keep in an airtight container for a couple days. Freeze to keep longer.
*The gluten free flour blend creates a slightly gritty texture in the final product, as most GF blends do. I didn't find it displeasing, but it is worth mentioning. *I used 3 Tbsp brown sugar and they turned out quite sweet. If you prefer a less sweet muffin, stick with 2 Tbsp. *Nutrition information is a rough estimate.