Spray inside of a large (6-quart) slow cooker with cooking spray. Add oats and pecans to the slow cooker; toss to combine.
In a small bowl, whisk together the remaining ingredients until smooth.
Pour over the oats and toss until the oats and nuts are completely coated.
Cover, and cook in a vented slow cooker (I just left my lid about halfway off to let the steam escape) on high for 2-4 hours, stirring every 30 minutes. Slow cookers run at different temperatures, so keep an eye on the granola as you stir. When it looks golden brown and toasted (but not burned), you know it’s done.
Stir in the cranberries and spread the granola onto waxed paper. Cool completely before storing in airtight containers.