Preheat oven to 350° F (177°C). Line your muffin tin with cupcake liners. (you may need two trays for this as the recipe will yield ~18 cupcakes)

In a large bowl, sift the flour, baking powder and salt and whisk to combine. Set aside.

In a separate large bowl using a hand mixer, beat the butter and sugar on medium-high speed until light and fluffy, 3-4 minutes.

Scrape down the sides and bottom of the bowl. Add the sour cream, dulce de leche and vanilla and continue to beat until completely smooth and combined.

Scrape down the sides and bottom of the bowl again. Lower the speed to medium-low and mix in the eggs, one at a time until just combined.

Add ⅓ of the dry ingredients and beat just until combined, then add ½ of the buttermilk and mix until just combined. Continue mixing in ½ of the remaining dry ingredients, remaining buttermilk, then remaining dry ingredients. Remember to mix after each addition before adding the next.

Pulse the caramel popcorn in a food processor until it forms very fine crumbs and add it to the batter. Fold until completely combined.

Spoon the cupcake batter into the prepared liners, filling each about two-thirds full. Bake in the preheated oven for 18-20 minutes or until a toothpick inserted into the center comes out clean. Allow the cupcakes to cool completely.

Allow to cool in pans for about 5 minutes, then transfer to wire rack to cool completely.