Add 1 teaspoon apple cider vinegar to almond milk and let sit while cooking berries.
Bring 1 cup of blueberries and coconut sugar to a simmer in a small pot. While it is cooking, mash the berries with spoon, and reduce the mixture for about 6 minutes until it is thickened. Allow to cool about 10 minutes.
In a large bowl, mix flour, baking powder, baking soda, lemon zest, and salt. *If using frozen berries, rinse them under cold water before adding them to the flour mixture now.
In a separate bowl whisk eggs with almond milk, maple syrup, applesauce, coconut oil, and vanilla.
Fold wet ingredients into dry ingredients along with 1 cup of remaining blueberries just until combined.
Fill muffin cups 2/3 full. Then spoon about a teaspoon of blueberry jam onto each muffin. Using a skewer, swirl cooked blueberries into the batter, then top with remaining batter, divided evenly.