Preheat your oven to 350°F (175°C). Line a 9-by-9-inch baking pan with aluminum foil, then spray with cooking spray or grease and flour the pan.

In a large mixing bowl, crack in the eggs and add the Greek blueberry yogurt, granulated sugar, canola oil, lemon zest (if using), and vanilla extract. Whisk until smooth and well-blended.

Gradually add the all-purpose flour and baking powder to the wet mixture. Mix gently until just combined; do not overmix.

Gently fold in the frozen blueberries using a spatula, ensuring even distribution without breaking them.

Pour the batter into the prepared pan, spreading it evenly. Sprinkle the remaining ¼ cup of blueberries on top.

Bake in the preheated oven for about 37 to 40 minutes, until the top is domed and a toothpick comes out clean.

Allow the cake to cool in the pan for 15 minutes before turning it out onto a wire rack to cool completely.

In a small bowl, whisk together the lemon juice, confectioners' sugar, and remaining vanilla extract until smooth.

Drizzle the glaze over the cooled cake. Serve immediately or store in an airtight container at room temperature or in the refrigerator for up to 5 days.