What exactly gives is that trademark hard fudginess to it but also that little bit of graininess and bite to it?

The fat? The flour? Does it have to have butter? What can I substitute to make it healthier but still retain that same texture and flavor? How far can I reduce the fat content to add protein for example, while keeping it a brownie?

>>21403568 (OP)
it's brown

the icing

>>21403568 (OP)
Fat and sugar makes the brownie, otherwise its chocolate bread.

To make it healthier use sourdough starter (spelt or something), less sugar (maple syrup, honey, coconut sugar), and maybe some whole plain yoghurt.

What makes it unhealthy mostly is the amount of sugar.

>>21403786
What if I want to jack up the protein and fiber content and lower the fat content?

Can it still resemble a brownie in texture and taste?

Can something like yogurt replace the fat texture-wise? I know casein produces a very unique texture in baking, unlike whey (which makes it bread-y).