Preheat oven to 350°F (175°C) and grease an 8.5 x 4.5-inch loaf pan with olive oil or parchment paper.
In a medium bowl, whisk together whole wheat pastry flour, baking powder, and salt.
In a large bowl, whisk together the Greek yogurt, honey, eggs, olive oil, lemon zest, lemon juice, and vanilla extract until well combined and smooth.
Gradually add the dry ingredients to the wet ingredients, folding gently with a spatula until just incorporated to avoid overworking the gluten.
Pour the batter into the prepared loaf pan and smooth the surface with a spatula.
Bake for 40 to 50 minutes, or until a skewer inserted into the center of the cake comes out clean.
Allow the cake to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before slicing.