I took a tissue sample from an outer layer of skin from onion.
The fungi has long white stalks/ mycelia with black sclerotia on the ends. This fungi grew so fast and filled up the entire plate within a week, you can see through it anymore, and it looks like it inhibited growth of other fungi as well because I don’t see anything else growing.
I believe it is Rhizopus stolonifer because of the obvious macro morphology of the black dots and white stems.