Cook corn syrup and sugar together in a large saucepan over medium heat, stirring to dissolve sugar. Bring mixture to a boil. Remove from heat. Stir in peanut butter and food coloring; mix well. Add cereal; stir until evenly coated.
Pour into two greased 8 or 9-inch round cake pans and pat into place. Cool at least 45 minutes, or until firm. Cut each circle into 8 triangles and remove from pan.
Melt chocolate over low heat, stirring constantly. Drizzle over cereal and top with candies. Use the chocolate to stick a peanut butter cup or pretzel on as the trunk of the tree.