Fungus on mulch?
Thank you for your question. This is a slime mold or Fuligo septica. A common name for slime mold is dog vomit fungus. Slime molds are not harmful to landscape plants and no health hazards are associated with them unless eaten. You can leave it to decompose in place, discard in a compost pile, household garbage, or a spot away from any existing mulch.
Here is more from Penn State https://extension.psu.edu/what-is-growing-in-my-landscape-mulch-mushrooms-slime-molds-and-fungus