For the pancakes: Whisk the egg, buttermilk and oil together in a large bowl. Add the Pancake Mix to the wet ingredients and whisk until just combined.
Heat a large pan or griddle over medium heat and grease with butter or oil. Pour the pancake mixture onto the griddle in 1-tablespoon portions to make 8 mini pancakes. Cook for 2 minutes. Flip the pancakes and cook for 1 minute more.
Place the pancakes on a cooling rack, and allow to cool completely. Repeat with the remaining batter to make 8 more.
For the chocolate sun butter: Melt the chocolate chips in a bowl in the microwave until melted, 40 seconds, or in a double boiler, and allow to cool. Stir the sunflower butter into the melted chocolate.
Spread 1 tablespoon of the chocolate sun butter on a pancake, and sandwich together with another pancake. Repeat with the remaining ingredients.
To freeze for later, place cooled sandwiches on a parchment-lined baking sheet. Freeze until solid, about 1 hour. Transfer to a freezer bag and store for up to 3 months.
Whisk together the flour, sugar, baking powder, baking soda and salt in a bowl. Store in an airtight container until ready to prepare pancakes.