Start by bringing your unsalted butter to room temperature.

In a mixing bowl, beat the softened butter using a stand mixer or hand mixer on medium speed for about 3-5 minutes until fluffy and pale.

Gradually add the sweetened condensed milk to the beaten butter, mixing slowly.

Continue to beat the mixture on medium-high speed for another 2-3 minutes until light and fluffy.

Add the vanilla extract and salt to enhance flavor and balance sweetness.

Mix on high for an additional minute to fully combine all ingredients.

Taste the buttercream and adjust sweetness if desired.

Transfer to an airtight container and refrigerate if not using immediately.