1. Preheat the oven to 350°F and line a baking dish with parchment paper.

2. In a bowl, cream 1 cup butter and 1/2 cup powdered sugar until fluffy.

3. Add 2 cups flour and 1/4 teaspoon salt, mixing until a dough forms.

4. Press dough evenly into the dish and bake for 20 minutes, until lightly golden. Let cool.

5. In a saucepan, combine 1/2 cup brown sugar, 1/2 cup butter, and 1 can sweetened condensed milk.

6. Cook over medium heat, stirring constantly, until thickened and golden (about 10 minutes).

7. Remove from heat, stir in 1 teaspoon vanilla extract. Pour over the cooled shortbread.

8. Let caramel layer set at room temperature or refrigerate to speed it up.

9. Melt 2 cups milk chocolate chips until smooth, then pour and spread over caramel.

10. Let bars cool and chocolate set. Cut into bars, squares, or bites to serve.