Start by beating the softened butter in a stand mixer or with a handheld mixer using a paddle or whisk attachment on medium-high speed for about 4-5 minutes until it turns a pale yellow color. Remember to scrape the bowl's sides if needed.

Next, turn off the mixer and add the powdered sugar and vanilla. Mix it all on low speed for about a minute until it's combined and has a crumbly texture.

After that, increase the mixer speed to medium and continue beating the mixture for about 3-4 minutes until it becomes light and fluffy.

Check the consistency of your frosting. If it’s too thick, incorporate a few tablespoons of milk or heavy cream, adding ½ tablespoon at a time until you achieve the perfect spreadable consistency.