
Preheat the oven to 350 degrees F. Line an 8x8 inch square pan with parchment paper and spray with nonstick cooking spray. Set aside.
Measure out 1 cup of shredded zucchini, then squeeze out all moisture.
In a large bowl, whisk together shredded zucchini, eggs, honey, lemon zest, lemon juice, and almond extract.
Add almond flour, oat flour, baking soda, and salt. Mix until well combined.
Toss blueberries with 2 tablespoons of oat flour, then fold into the batter.
Pour batter into the pan. Bake for 30-35 minutes. Allow the cake to cool completely before frosting.
Beat together butter, powdered sugar, lemon juice, and lemon zest. Spread frosting on the cooled cake and garnish with blueberries.