Preheat your oven to 350°F (175°C) and grease a 9-inch round cake pan.

In a medium saucepan over medium heat, melt ½ cup unsalted butter and 1 cup of brown sugar until smooth and bubbly.

Pour the caramel mixture into the greased cake pan and spread evenly.

Arrange the pecan halves over the caramel layer evenly.

In a medium bowl, whisk together 1 ½ cups of all-purpose flour, 1 ½ teaspoons of baking powder, and ¼ teaspoon of salt.

Cream ½ cup of unsalted butter with ¾ cup of granulated sugar until light and fluffy.

Add 2 large eggs one at a time, then stir in 2 teaspoons of vanilla extract.

Gradually add the dry ingredients and ¾ cup of milk alternately until just combined.

Pour the batter over the pecans and caramel layer and smooth the top.

Bake for 35–40 minutes, until a toothpick comes out clean.

Cool the cake in the pan for 10 minutes, then invert it onto a plate.

Slice and serve warm, optionally with ice cream.