Hi
@ChefDan420! I think you're having "Leucocoprinus birnbaumii mushrooms". Spores must have been introduced by contaminated medium, or by airborne / clothes / some element coming from the great outdoor. Good news: they should be harmless to your plants. Bad news: they're nearly impossible to remove, even fungicides are useless against them. Final advice: don't eat them!!! You will risk severe diarrhea, nausea and vomiting (at worst, death). And if you have kids or pets, you want obviously to keep them away from these. Hope this will help, keep us up-to-date and happy growing 👊