Beat 2 cups of unsalted butter on medium speed for 30 seconds until smooth with a paddle attachment / stand mixer or a hand mixer.
Mix in 1 Tbsp vanilla extract or vanilla bean paste and ½ tsp salt on a low speed.
Slowly add in 7 cups of powdered sugar while mixing slowly on the lowest setting. Halfway through add in 3 Tbsp of heavy cream or milk to make it easier to mix. I like to place a kitchen towel over my mixer to contain any powdered sugar clouds.
Mix on low until the ingredients are fully incorporated and the desired consistency is reached. Scrape the sides and bottom of the bowl as needed with a rubber spatula.
If the frosting is too thick, add in additional cream (1 Tbsp at a time). If the frosting is too thin, add more powdered sugar (a quarter of a cup at a time).
If you plan to color the buttercream, add in the gel food coloring once the frosting is fully mixed and beat on low until it reaches the desired color.
To make the frosting extra smooth, stir it by hand with a rubber spatula for a minute or two right before you use it. It's an arm workout, but it's worth it! Push the frosting back and forth and spread it around the side of the bowl. This will push out any extra air and make it easier to smooth onto cakes or pipe with.
