Preheat oven to 350º F. Spray a 9x5 loaf pan with cooking spray; set aside.
Combine flour, baking powder and salt in a medium bowl.
In another bowl, combine yogurt, Truvia, eggs, lemon zest and vanilla extract. Stir to combine. Slowly whisk in the flour mixture. Fold in coconut oil. Pour into prepared pan and bake for about 50 minutes or until a toothpick comes out clean.
While that's cooking, heat lemon juice and Truvia in a small saucepan until the sugar dissolves and the mixture turns clear. Set aside to cool.
When cake is finished, let cool for 5 minutes. Poke the top of cake with toothpick several times and then pour the lemon-sugar mixture over the top of the cake. Set aside and let cool.
When cake is cool and lemon-sugar mixture is all soaked in, lightly turn pan and gently remove cake onto a plate.
Mix some powdered sugar in with a little bit of water and stir. Lightly drizzle over cake. Tastes great without the glaze! Cut into slices and serve. Enjoy!