Preheat your oven to 350°F (175°C). Lightly grease a loaf pan. This ensures your loaf releases easily.
In a large bowl, whisk together the dry ingredients. This includes the gluten-free flour, protein powder, sugar, leavening agent, and salt.
In a separate bowl, combine the wet ingredients. This includes the eggs, oil, lemon juice, and lemon zest. Whisk until smooth.
Pour the wet mixture into the dry ingredients. Stir until just combined. Be careful not to over-combine the batter.
Gently fold in the blueberries. Distribute them evenly throughout the batter.
Transfer the batter to your prepared loaf pan. Spread it evenly.
Place the pan in the preheated oven. Cook for 50-60 minutes. A toothpick inserted into the center should come out clean.
Let the loaf cool in the pan for 10 minutes. Then, transfer it to a wire rack to cool completely. Enjoy your homemade lemon pound cake!