Combine oats, vanilla, pie spice, salt, brown sugar, and milk in a microwave-safe bowl. Make sure that the bowl is large enough because the milk and oatmeal will bubble up a little bit while in the microwave.
Microwave on high for 2 minutes.
Stir in sweet potato and microwave for an additional 60 seconds.
Stir, allow to cool for a few minutes, and top with pecans before eating.