1. Preheat the oven to 350°F (175°C) and line an 8×8-inch baking pan with parchment paper.

2. In a large bowl whisk together sourdough discard, melted butter or coconut oil, coconut sugar, egg, and vanilla until smooth.

3. In a separate bowl combine whole grain flour, rolled oats, baking powder, salt, and cinnamon.

4. Fold the dry ingredients into the wet mixture until just combined, avoiding overmixing.

5. Spread the batter evenly in the prepared pan, smoothing the top with a spatula.

6. Bake for 20–25 minutes until the edges are golden and the center is set.

7. Allow the bars to cool in the pan on a wire rack for 10–15 minutes.

8. Lift the bars from the pan using the parchment overhang and cut into 9 squares.

9. Serve warm or at room temperature and store leftovers in an airtight container.