In a large bowl, combine oats, chopped pecans, and dried cranberries; set aside.

In a medium saucepan over medium heat, combine sugar, butter, milk, and a pinch of salt. Stir constantly until butter melts and mixture comes to a gentle boil. Let boil 1–2 minutes, stirring continuously.

Remove from heat and stir in vanilla extract and cinnamon if using.

Pour the hot sugar mixture over the oat, nut, and cranberry mixture. Stir quickly until everything is coated evenly.

Using a spoon or cookie scoop, drop portions onto a parchment-lined baking sheet. Work quickly before the praline cools and hardens.

Let cookies sit at room temperature for at least 30 minutes to fully set.