Preheat your oven to 350°F. Line a 12-cup muffin tin with cupcake liners.

In a small saucepan, melt 1 cup of unsalted butter over medium heat, stirring occasionally. You'll hear it start to bubble and foam—that's totally normal. Keep stirring until the milk solids turn golden brown and smell absolutely incredible (about 5-8 minutes). This is your brown butter magic.

Pour the brown butter into a bowl and let it cool for about 5 minutes. Measure out 1/2 cup of the cooled brown butter and set aside; reserve the remaining brown butter for the frosting.

In a large mixing bowl, whisk together the 1/2 cup cooled brown butter and light brown sugar until well combined, about 1 minute.

Add the eggs and vanilla extract, then mix until smooth and pale, about 2 minutes.

Stir in the sour cream and pumpkin puree until completely combined and smooth.

In a separate bowl, whisk together the all-purpose flour, baking powder, pumpkin pie spice, cinnamon, and salt.

Gently fold the dry ingredients into the wet ingredients until just combined—don't overmix. A few flour streaks are totally fine and will keep your cupcakes tender.

Using an ice cream scoop or spoon, divide the batter evenly among the 12 cupcake liners, filling each about two-thirds full.

Bake for 20-22 minutes, or until a toothpick inserted into the center comes out clean or with just a few moist crumbs. Don't overbake.

Remove from the oven and let the cupcakes cool in the tin for 5 minutes, then transfer to a wire rack to cool completely. This is important—frost them while they're still slightly warm, and they'll set beautifully.

In a mixing bowl, beat the reserved brown butter and room-temperature cream cheese together until smooth and fluffy, about 2 minutes.

Gradually add the powdered sugar, a cup at a time, beating well after each addition to avoid lumps.

Add the vanilla extract and salt, then beat until light and airy, about 2-3 minutes.

Once the cupcakes are completely cool, pipe or spread the frosting generously onto each one.

Drizzle about 1 teaspoon of salted caramel on top of each frosted cupcake, then swirl it gently with a knife or offset spatula for that gorgeous marbled effect.