In a saucepan, combine 1 cup of raspberries with 2 tablespoons of water over medium heat. Cook for about 5 minutes until smooth. Cool completely.

In a mixing bowl, whip 1 cup of softened unsalted butter on medium speed for 3 to 4 minutes until light and fluffy.

Gradually add 1 cup of powdered sugar to the whipped butter, mixing on low speed until just combined.

Slowly add 2 tablespoons of cooled raspberry puree and 1.5 teaspoons of vanilla extract. Mix on low speed.

Gradually add the remaining powdered sugar in increments, alternating with raspberry puree, mixing on low speed.

Add 3 tablespoons of heavy whipping cream when thick, mix on medium speed for 1-2 minutes. Add a pinch of kosher salt.

Increase mixer speed to medium-high and whip for another 4 to 5 minutes until fluffy.

Use your frosting immediately or store in an airtight container in the refrigerator for up to 7 days.