From the Joy of Cooking (All New All Purpose)
Position a rack in the center of the oven. Preheat to 350˚F. Grease a 9 x 5 inch loaf pan.
Whisk together in a large bowl:
3 cups all-purpose flour
4 tsp baking powder
1 tsp salt
½ tsp baking soda
Add and toss to separate and coat with flour:
1 cup coarsely shredded zucchini (or any summer squash)
¾ cup grated cheddar cheese
¼ cup chopped scallions (or chives or shallots)
3 tbsp chopped fresh parsley
1 tbsp snipped fresh dill, or 2 tsp dried
Whisk together in another bowl:
2 large eggs
1 cup buttermilk
4 tbsp (1/2 stick) warm melted unsalted butter or vegetable oil
Add to the flour mixture and mix with a few strokes just until the dry ingredients are moistened. Do not overmix; the batter should not be smooth. Bake until a toothpick inserted in the center comes out clean, 55 to 60 minutes. Let cool in the pan on a rack for 5 to 10 minutes before unmolding to cool completely on the rack. Serve warm with butter.