Combine the quick-cooking oats, chia seeds, dry milk powder, sugar, and kosher salt in a large bowl or airtight container. Stir thoroughly to distribute all ingredients evenly, breaking up any clumps in the milk powder. This dry mix can be made in larger batches and stored in an airtight container for up to 2 weeks, making weekday breakfasts incredibly quick. I like to whisk the mixture rather than just stir it to ensure the milk powder is fully incorporated and won't clump when liquid is added.

In a bowl or mason jar, combine 1/2 cup of the dry oat mix from Step 1 with 3/4 cup cold water or milk (I prefer using milk for extra creaminess and protein, but water works fine too). Stir well to combine, making sure all the oats and chia seeds are fully hydrated and there are no dry pockets. The mixture will seem slightly loose at this point, which is exactly what you want.

Cover the bowl or jar with a lid or plastic wrap and refrigerate for at least 10-15 minutes, though overnight (8 hours or more) is ideal. The longer the oats sit, the creamier and more pudding-like the texture becomes as the chia seeds absorb liquid and release their natural thickening properties. In the morning, stir the oats and add a splash more liquid if needed to reach your desired consistency.