Start by preheating the oven to 350°F and spray a 9×5-inch loaf pan with non-stick spray. This step ensures your loaf doesn’t stick, making for easy removal once it’s baked.
In a large mixing bowl, whisk together the flour, sugar, baking powder, baking soda, and salt. This dry mixture forms the base of your loaf.
Take another bowl and whisk together the yogurt, oil, egg, egg whites, and lemon zest. Make sure it’s well blended; this mixture adds moisture and flavor.
Carefully pour the wet ingredients into the dry ingredients. Stir gently until just combined. Be careful not to overmix; a few lumps are okay!
Now, fold in the fresh raspberries with a light hand to avoid breaking them too much. The aim is to keep the berries whole so they burst with flavor in each slice.
Pour the batter into your prepared loaf pan, smoothing the top gently with a spatula. It should be even; this helps it bake uniformly.
Place the pan in your preheated oven and bake for about 50 minutes. You'll know it's done when a toothpick inserted into the center comes out clean.
Once baked, allow the loaf to cool in the pan for 10 minutes. This resting period helps it set up a bit before transferring it.
After 10 minutes, gently remove the loaf from the pan and let it cool completely on a wire rack. This step is crucial; cooling it fully helps maintain the loaf's texture.