To make meringue mushrooms: Prepare the Swiss meringue as described until fully whipped (step 3). Transfer the meringue to two pastry bags, each fitted with a small round tip: 1/4", 1/2", and 5/8" all work well. Use the larger of the two tips to pipe dome-shaped rounds ranging in size from 1/2" to 2" in diameter onto a parchment-lined baking sheet. (These are the mushroom caps.) Use the remaining meringue to pipe upright cylinders with flat tops, about 3/4" wide and 1 1/2" tall. Use a damp fingertip to smooth any peaks. (These are the mushroom stems.) Bake as directed above (step 8). To assemble, brush the caps and stems with cocoa powder, then brush or pipe a little melted chocolate over the bottom of each cap and dip the top of each stem in chocolate. Join the pieces together. (For extra insurance, create a small hole in the cap with a toothpick, then brush or pipe melted chocolate in and around the hole and plug it with a stem.) Allow the chocolate to set, then use the meringue mush
Made 3/4 of the recipe and caught it just before the marshmallows caught fire. All I can say is daaayuuuummmm! Nobody was expecting that flavor combo. I could hide myself in a closet and eat the entire casserole.
Decided to add another 20g of peanut butter and 1 tsp of this cocoa powder to the mousse mixture. Used approximately a 50/50 combo of Ghirardelli bittersweet baking chocolate and semi-sweet chocolate chips for the ganache, thinned with the stirred up coconut milk. I think it took about 60g to thin it down sufficiently .