Preheat oven to 375°F (190°C) and grease a muffin tin.
In a bowl, mix flour, butter, sugar, and salt until crumbly. Press into muffin tin as crust.
In another bowl, mix peaches, brown sugar, cinnamon, cornstarch, and vanilla. Spoon into crusts.
Mix oats, pecans, and melted butter; sprinkle over peach filling.
Bake for 20-25 minutes or until golden brown.
Cool before serving. Enjoy warm or with a scoop of vanilla ice cream!