Preheat waffle iron to desired level of heat - I prefer mine crispy.
Combine almond milk and vinegar in a large liquid measuring cup or small mixing bowl and let set for a few minutes to curdle/activate. Prepare flax egg in a separate dish and let rest 5 minutes.
To the almond milk and vinegar add flax eggs, melted butter, vanilla extract, lemon juice and zest, and agave nectar or maple syrup and whisk. Set aside.
Add dry ingredients to a large mixing bowl and whisk until well combined. Then add wet ingredients to dry and mix until well incorporated. Fold in blueberries.
Once waffle iron is ready, generously coat with non-stick spray or vegan butter and pour on about ⅓ cup of batter. Cook according to manufacturer instructions and then remove and place on a baking rack in a 200-degree F (93 C) oven to keep warm. Do not stack - keep them in a single layer to keep crispy.
Serve immediately with desired toppings. Store leftovers in a freezer safe bag and reheat in the toaster for best results. Will keep in the freezer for up to a couple months, although they’re best when eaten within the first couple weeks.
Suggested toppings: almond butter or vegan butter, flaxseed, bananas, blueberries, maple syrup.