First, combine all sunflower butter bar ingredients in a large mixing bowl, and stir thoroughly to combine. If it is a little dry or crumbly and not holding together like a dough, add more non-dairy milk, 1 tablespoon at a time.
Next, press the mixture into a 6x6 baking dish.
Top with melted chocolate until the batter is fully covered, add flaky sea salt if desired. Then refrigerate or freeze until the chocolate is hardened. Slice into bars to serve.