In a medium sized mixing bowl, whisk together the flour, oats, baking soda, baking powder and salt. Set aside.

In the bowl of a stand mixer, cream the butter, brown sugar, and granulated sugar together until light and fluffy, 3-5 minutes. 

Mix in the eggs and mix until combined. 

Mix in the sourdough discard and vanilla and mix until combined. 

Add in the dry ingredients and mix until just combined.

Stir in the raisins.

Chill the dough for at least 1 hour. The dough should feel tacky but not overly sticky.

Preheat the oven to 350 and line two baking sheets with either parchment paper or silpat mats.

Scoop 2 Tablespoon sized portions of dough and roll them into a ball.

Place the cookie balls 2” apart on the prepared baking trays.

Bake for 10-12 minutes, until the edges are just starting to turn golden brown.

Allow to cool for 5 minutes on the baking tray before moving to a wire rack to finish cooling.