In a large mixing bowl, add the eggs, yogurt, sugars, oil, and vanilla extract. Mix well with a whisk.
Sift in the flour and cocoa powder. Add the baking powder, baking soda, and salt on top of the flour and mix it in. Mix all of the dry ingredients into the wet ingredients, switching the whisk for a spatula as the mixture thickens. Stir only until just combined.
Add chocolate chips and stir.
Add batter to a 9x5 loaf pan. Sprinkle additional chocolate chips on tips if you want to.
Bake for about 40 - 50 minutes, or until a skewer comes out mostly clean. Let cool for 10 minutes and then move the loaf to a wire rack to let it cool to room temperature. An underbaked cake will collapse in the center.
Slice into 10 slices and serve as is or buttered.
Video
Notes
Sift the cocoa powder: this is so important in baking for two reasons.
1. Cocoa powder clumps, if you don't sift it, you'll have clumps of cocoa in your batter because
2. Cocoa powder is hydrophobic - this means it's actually kind of water-resistant and is harder to mix in. Sifting helps, as does gently folding it in with a rubber spatula.
light loaf tin: using a light-colored metal baking tin helps your quick bread cook evenly and not cook too quickly. I use a non-stick loaf pan, but you can spray yours with cooking spray or line it with parchment paper if you've had trouble with sticking before. Mine hasn't stuck before and I've used this recipe for muffins without using paper liners and it never sticks.
You can make 12 muffins instead of the loaf cake with this batter. Bake for about 20 minutes.Store the chocolate loaf cake in an airtight container at room temperature for 3-4 days. You can also store it in the fridge if you prefer.To freeze the loaf, slice it and wrap the slices individually. Freeze for up to three months. Thaw in the fridge overnight or on the counter for a few hours.