Grease and flour an 8 ½ x 4 ¼ x 2 ½ inch baking pan. Preheat the oven to 350 degrees. In a bowl mix 1 ½ cups flour, salt, and baking powder. Set aside.
In another bowl whisk together yogurt, eggs, sugar, lemon zest, oil and vanilla extract. Slowly mix the wet and dry ingredients together into one bowl.
Lightly toss blueberries in 1 tablespoon of flour to coat, and fold them gently into the batter. Pour the batter into your baking pan and bake for 50-60 minutes or until done. Stick a toothpick in the loaf and if it comes up clean, it’s done. While the loaf is baking cook 1/3 cup lemon juice and 1 tablespoon of sugar until sugar is dissolved. Set aside.
When the loaf is done allow it to cool for 10-15 minutes, and place on a cooling rack. When the loaf is still warm pour the lemon-sugar mixture over it and allow it to soak in. Allow to fully cool.