Combine the first four ingredients in a medium-sized saucepan.
- Heat over medium heat, stirring until sugar is dissolved.
- Clip candy thermometer to the side of pan.
- Bring mixture to soft ball stage (234º).
- Remove from heat and let cool 15 minutes or so.
- Add vanilla and pumpkin pie spice, and beat syrup vigorously until it becomes opaque and begins to crystallize. An immersion blender is perfect for this step, but a fork works nicely too.
- Stir in oats and drop by the spoonful onto parchment paper.
- Let cool.
- Enjoy!