Preheat oven to 350 degrees F (175 degrees C). Spray muffin cups with cooking spray.
Mix butter, seaweed, and sea salt together in a bowl until smooth. Mix flour, confectioners' sugar, eggs, honey, coconut oil, and cinnamon into butter mixture until batter is just mixed; pour into the prepared muffin cups.
Bake in the preheated oven until the sides of the muffins begin to darken, 12 to 15 minutes.