Mix the peanut butter, Nutella, butter, and powdered sugar in a bowl.
Take a pretzel stick and mold some of the peanut butter mixture around it, forming a slight cone shape.
Holding it steady by using the tip of the pretzel as a handle, start inserting pieces of cereal into the peanut butter mixture in a symmetrical pattern around the stick. Add more cereal pieces, staggering them as you move upward, until you get near the top.
Cut several cereal pieces into triangles and add those to the top (most pinecone scales get smaller toward the end.)
If your pinecone is getting too tall (like mine were), cut off the top of the pretzel and add a dollop of peanut butter mixture to cover it. Insert a few more triangle pieces of cereal into the top of the pinecone.
For a “snowy” effect, dust the pinecone with powdered sugar.