In a large bowl, beat the eggs, egg yolk and sugar until creamy.
In a medium bowl, whisk together the flour, salt and baking powder.
Slowly combine the dry ingredients to the liquid ingredients until well combined.
Fold in the mini chocolate chips.
Line the bottom of a 4 or 5 qt slow cooker with parchment paper and spray with cooking oil.
Pour the batter on top of the parchment paper.
Cover and cook on HIGH for 2 hours or until the middle has set.
Remove the cake by pulling up on both sides of the parchment paper.
Remove the parchment paper and allow to cool. Slice and enjoy!