If your mushroom pumpkin is starting to look droopy and shriveled, give it a cold-water bath to revive it. Just dunk the whole pumpkin in a cooler of ice water for up to eight hours to rehydrate and firm up. Don't try this tip with real mushrooms though: They'll soak up water like sponges and become less tasty to eat!
1. Clear out the inside of your pumpkin by scooping out the fibrous strands and seeds with a stiff metal spoon or scoop. Pare down the side of the pumpkin you're planning to carve by scraping it to a 1-inch thickness.
2. Secure your mushroom stencil to the pumpkin's exterior with clear tape, flattening the paper with your hands as best you can. Perforate the stencil lines with a needle tool, piercing through both the paper and the pumpkin skin underneath. (Hint: Keep pin holes closely spaced, ideally within 1/8 inch of each other.) Pull off the pattern.
3. Etch the mushroom spots and cap line with a chisel or razor blade, removing the pumpkin's top layer of skin from these areas. Carve areas surrounding the mushrooms by using a skinny crafts knife to saw completely through the pumpkin wall, following the pin hole cutting guide.
4. Nudge the carved sections outward by pressing on them from inside your pumpkin. Give your mushrooms a pretty backlit glow by placing a battery-operated candle inside the pumpkin cavity.