Begin by preparing your slow cooker: combine the white candy coating, chow mein noodles, and dry roasted peanuts into the pot. Ensure that the ingredients are well-distributed.

Cover the slow cooker with its lid and set it to HIGH heat. Allow the mixture to melt for about 1 hour, stirring gently halfway through.

After the melting process, stir the mixture well to evenly coat the chow mein noodles and peanuts with the melted candy coating. Drop spoonfuls onto a lined baking sheet.

Before the chocolate hardens, sprinkle Halloween sprinkles generously on each haystack.

Once all the haystacks are formed and decorated, place the baking sheet in the refrigerator for about 1 hour to chill and set.