Preheat oven to 350°F. Grease a 9x4 inch loaf pan and line with parchment paper. Line a 6-cup muffin tin with papers OR oil a mini loaf pan.
In a bowl, sift together dry ingredients and set aside.
In a large bowl, beat eggs; beat in yogurt, buttermilk, oil, sugar, and vanilla. Combine well. Stir in grated zucchini.
Carefully blend flour mixture into the wet ingredients and stir until combined.
Scoop batter into 6 muffin cups (or mini loaf pan) and pour the rest into the 9x4 loaf pan. Bake for approximately 50 minutes or until a toothpick inserted in the center comes out clean.
Remove from oven and cool 10 minutes in the pan. Remove from pan and cool on wire rack. Cool loaf completely before cutting.