Use any food coloring you like to create these chewy snakes.
In a large saucepan over low heat, melt peanut butter, butter, and marshmallows, stirring until smooth, about 5 minutes. Remove from heat; stir in a few drops food coloring, then add cereal. Coat a 9 x 9-inch pan with cooking spray, then spread mixture evenly in the pan. Let cool 20 minutes. Invert pan on a cutting board and slide out the cooled square. Cut it into about 8 long rectangles. Mold each rectangle into the shape of a snake and press in 2 raisins for eyes and a pointed sliver of fruit leather for the tongue.
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