why my brownies taste bitter? I made brownies with the recipe of this:

egg           : 2

coco powder   : 1/2 cup

white flour   : 1 cup

milk          : 1 cup

baking powder : 1 tea spoon

oil           : 1/2 cup

sugar         : 1 cup

then i put oil, egg, and sugar in the bowl and beat it then i add coco powder and white flour and again beat them all for 5 minutes. Then i add milk and start beater. And then i spreading less oil in the dish and then add my ready brownies in the dish.Then i put brownies in microwave oven for 8 minutes for bake.

This is the recipe that i made but the brownies which i made is always bitter. Whenever i made it taste bitter a lot but why?

I don't know what step i done wrong can u please let me know what i can do that my brownies taste not bitter anymore.

How can it taste changes?
Unsweetened Cocoa powder is a very bitter ingredient, and 1/2 a cup of it seems like a lot considering the ratios. If you want your brownies less bitter then you may want to reduce the cocoa some, or add more sugar, or do both. Try reducing your cocoa by 2 tbsp and adding 2 tbsp more sugar, adjust the ratios that way until you have the right balance.