Cultured butter is a rich, tangy, and creamy spread made by fermenting cream with yogurt before churning. It's more flavorful and sophisticated than regular butter, perfect for spreading on fresh bread or using in recipes.
Pour all of the heavy cream into a mixing bowl. Add all of the yogurt and stir well to combine.
Cover the bowl and place it in a warm spot. Let it sit overnight or for about 12 hours, until the mixture thickens and becomes tangy, like yogurt.
Once fermented, refrigerate the cultured cream until it is completely cold. This helps with the butter-making process.
Pour the cold cultured cream into a stand mixer. Whip on medium-high speed until it first becomes whipped cream, then keep going until the fat separates from the liquid. You'll see yellow butter and milky buttermilk.
Strain off the buttermilk and save it for another use, like baking bread. Place the butter in a bowl.
Pour cold water over the butter and gently massage it to remove excess buttermilk. Replace the water and repeat a few times until the water runs clear.
Knead the butter a few more times to remove as much water as possible. If you like, sprinkle in some salt for flavor and knead to combine.
Place the butter on baking paper. Use a wooden mat for rolling kimbap (or your hands) to shape it into a stick. Twist the ends of the paper to seal.
Store the shaped butter in the fridge until ready to use. Enjoy your homemade cultured butter on fresh bread or in recipes!