Preheat your oven to 375°F, grease a 9 x 9 inch square or 5 x 8 inch rectangular casserole dish with a bit of coconut oil.
Combine the flax seeds and warm water in a small bowl, and set aside.
In a large bowl, combine the oats, walnut pieces, cinnamon, baking powder, and salt. Stir to combine.
In a medium bowl, combine the almond milk, orange zest and juice, and maple syrup. Add the flaxseed mixture, and stir to combine.
Scatter a handful of cranberries over the bottom of your casserole dish, followed by about half of the oat mixture. Add the remaining cranberries, and finish with the remaining oat mixture.
Pour the wet mixture over the oats, and give the casserole dish a little shake to ensure it has reached all of the nooks and crannies in there.
Bake for 35 - 45 minutes, until the top is puffed and golden.
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