Preheat your oven to 350°F. Line two baking sheets with parchment paper; set aside.
In a food processor, add the oats and pulse until fine crumbles, the size and texture of oat flour. (See notes if you have oat flour)
Add the flour and flaxseed, and pulse until well blended, about 30 seconds.
Add the melted & cooled coconut oil, and pulse to combine. Then add the water and pulse just until combined.
Add the blueberries and pulse just until combined and the dough starts to form into a ball, about 30 seconds. Remove the bowl from the food processor, carefully remove the blade.
Lightly dust a clean countertop or other large, clean, flat surface with flour. Turn out the dough onto the surface and shape into a ball.
Using a rolling pin, roll out the dough until it is even and about ¼" to ⅙" thick.
Using a dog-themed cookie cutter, cut out shapes and place the cutout dough onto the prepared baking pan, leaving about one inch between each treat. Gather extra dough, re-roll on the floured surface, and continue to cut out shapes until you've used up all the dough.
Bake at 350°F for 22-28 minutes, just until the edges are slightly golden brown and the centers are cooked through.
Allow to cool at room temperature before feeding to your dog or storing.
Notes
Makes approximately 28 dog treatsOats: if you have oat flour, you can substitute that for the oats and simply add it to the food processor. The dog treats won't have the same texture, but should bake up in the same amount of time. Coconut oil: Measure out coconut oil in its solid form according to the recipe measurements, then microwave for 20 to 30 seconds to melt. Allow the oil to cool at room temperature before adding to the batter.Storage: Store in an airtight container at room temperature for up to 3 days or in the refrigerator for up to one week. If you want to store them for longer than that, you can place in a freezer bag or other freezer safe container for up to 3 months.