Preheat the oven to 350°F. Line a 12-count cupcake tin with paper liners and lightly spray with nonstick spray. Set aside.
Mix the pineapple juice, butter, eggs, vanilla, pineapple extract (if using), and crushed pineapple pieces in a large bowl.
1 cup pineapple juice, 1 cup unsalted butter, 6 large eggs, 1½ teaspoons pure vanilla extract, ½ cup crushed pineapple, 1 teaspoon pineapple extract
Add in the cake mix and mix until just combined.
26.5 ounces yellow cake mix
Fill each cavity in the prepared muffin tin ¾ of the way full with batter.
Place in the preheated oven on the middle rack. Bake for 22 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.
Once baked, remove from the oven and place on a wire cooling rack to cool.
Once cool enough to touch, remove cupcakes from the tin and repeat the baking process with the remaining batter.
Once all cupcakes are baked, cool them completely before frosting, about 1-2 hours.