Preheat oven to 350 degrees Fahrenheit. Line an 8x8 baking dish with parchment paper.
In a large bowl, mix milk, eggs, honey, baking powder, vanilla, salt, and cinnamon.
Add oats, chopped walnuts, and blueberries. Stir gently to combine.
Pour into 8x8 and bake 30-40 minutes until a toothpick inserted in the center comes out mostly clean.
Let cool slightly before slicing into 9 squares. Add a drizzle of honey and any other desired toppings (more walnuts, perhaps?) and enjoy!
Store in an airtight container in the fridge for up to a week. Enjoy cold or reheated!