Preheat oven to 325 degrees. Line 2 baking sheets with parchment paper.
In a medium sized bowl, combine flour, cocoa powder, baking powder, baking soda and salt. Mix well with a whisk or fork until well combined. Set aside.
In the bowl of an electric mixer, combine sunbutter and oil. Beat on medium speed for 2 minutes. Scrape down the bowl.
Add the sugar and brown sugar. Beat until light and fluffy, about 2 minutes. Scrape down bowl.
Add the vanilla.
Add the egg and egg yolk. Mix for about 60 seconds on medium speed. Scrape down the bowl.
Turn your mixer to the lowest setting. Add the flour mix in. Stir until it is about half incorporated.
Add the sunflower seeds and ½ C of the chocolate chunks. Continue mixing on lowest setting until all the flour is incorporated.
Scoop dough into golf ball sized portions. Place onto prepared baking sheets leaving about 2 inches between cookies. Flatten them slightly into discs about ¼" thick. Add the remaining ¼ C of chocolate chunks on top of cookies.
Bake in preheated oven 11 minutes. Cool on cookie sheets for 2 minutes. Move to wire rack to cool completely.
Store in airtight container at room temperature for 3-4 days.