Preheat the oven to 350 degrees. Grease a loaf pan and line it with parchment paper.
Whisk the flour, baking powder, baking soda, and salt in a bowl and set aside.
Beat the eggs and sugar for a full 2 minutes in a stand mixer.
Add the butter, vegetable oil, and lemon olive oil and beat again.
Add the vanilla extract, lemon extract, lemon zest, and lemon juice, and mix again on medium.
Add the sour cream and mix until combined.
Mix the dry ingredients into the wet ingredients until just combined.
Toss the blueberries with 1 tablespoon of gluten free flour and gently fold them into the batter.
Pour the batter into your prepared loaf pan and bake at 350 degrees for 45 to 55 minutes until a toothpick inserted into the center comes out clean.
Set the baked loaf cake aside to cool on a wire rack.