Preheat oven to 350°F (176°C). Use a paper towel to coat a loaf pan with coconut oil. Set pan aside.
Mix flour, baking soda, salt, and poppy seed together in a small bowl. Set aside.
Blend coconut oil, agave, yogurt, vanilla, and milk. Beat in lemon juice and eggs.
Stir dry ingredients into wet ingredients until combined. Do not overmix!
Pour batter into prepared pan and bake for 30 - 35 minutes until a toothpick inserted into the center comes out clean.
Let cool in pan for 10 minutes before removing loaf from pan and cooling fully on a wire rack. You may need to slide a knife between the loaf and pan to loosen before removing.
Wait until loaf is fully cool to coat with glaze. Make glaze by whisking together powdered sugar, vanilla, and lemon juice. Add lemon juice a little at a time until the consistency is thick but easily pourable. Drizzle glaze over bread and let sit for 10 - 15 minutes before cutting to let glaze harden.