Preheat oven to 350°F. Line a 12-cup muffin tin with cupcake liners.
In a medium bowl, whisk together flour, baking powder, baking soda and salt.
In a large bowl, using an electric mixer, beat butter and sugar until light and fluffy. Add eggs, one at a time, beating until combined. Add vanilla extract and mix until combined.
Add guava paste and mix until combined.
Add the flour mixture and buttermilk alternately, starting and ending with the flour mixture. Beat until just combined.
Divide the batter evenly among the cupcake liners. Bake for 18-20 minutes, or until a toothpick inserted in the center comes out clean.
Let cool in the pan for 10 minutes before transferring to a wire rack to cool completely.
Interesting Facts
Guava paste is a sticky, sweet jam made from guava, sugar, and pectin.
These cupcakes are traditionally served in Cuba with a sprinkle of powdered sugar.
The cupcakes can be stored in an airtight container and kept at room temperature for up to 3 days.