For Pancake Mix:
Use immediately or store in an airtight container for up to 2 months. Use immediately or store in an airtight container for up to 2 months.
In a large bowl, combine 2 cups of the pancake mix and 2 tbsp. flaxseed. In a small bowl, whisk the buttermilk, eggs and 4 tbsp. melted butter. Add the egg mixture to the pancake mix and whisk until combined.
Heat a large cast-iron skillet or griddle over medium. Ladle 1/4-cupfuls of batter into the pan and cook until brown on bottom, about 4 minutes. Flip and cook about 4 minutes more. Transfer pancakes to a plate and repeat with the remaining batter. Serve with butter and maple syrup, if using, or fruit toppings.