Preheat the oven to 350°F (180°C).
Grease or line a loaf pan with parchment paper. In a large bowl, whisk together the eggs, yogurt, oil, vanilla extract, sugar, and salt until smooth and well combined.
Add the vanilla protein powder, flour, and baking powder. Mix until just combined and no lumps remain.
Pour the batter into the prepared loaf pan and smooth the top.
Bake for about 45-50 minutes, or until a toothpick inserted into the center comes out clean.
While the cake is still warm, pour 2–3 tablespoons of maple syrup evenly over the top and let it soak in.
Let the cake cool completely before slicing.