Preheat the oven to 350°F and line a baking sheet with parchment paper.

Add the rolled oats to a blender or food processor and pulse until they become a fine oat flour.

In a medium bowl, whisk together the applesauce, egg, and honey until smooth.

Add the oat flour and whole wheat flour to the wet mixture and stir until a soft dough forms, adding a small splash of water only if the dough is too dry.

Gently fold in the blueberries until evenly distributed throughout the dough.

Lightly flour a work surface and roll the dough to 1/4-inch thickness.

Use a small cookie cutter or a knife to cut the dough into bite-sized shapes or squares.

Arrange the dough pieces on the prepared baking sheet, leaving a little space between each biscuit.

Bake for 15 to 20 minutes, until the biscuits are firm and lightly golden on the edges.

Let the biscuits cool completely on the baking sheet or a wire rack before serving to your dog.