The Energy Crystal

That's not a Diamond Doughnut, 

that's an Energy Crystal 

and it came from the Spaceship where the 2 Aliens 

that are purple and green in  

Ducktales Episode called "Superdoo!". 

Doofus thought it was a Diamond Doughnut, 

but it's not, 

it was an Energy Crystal that came from the Alien's Spaceship. 

This Energy Crystal would give Doofus all Superpowers.