I make crème fraîche a lot because it’s delicous as a dollop and as an ingredient. Serve it next to a slice of fruit tart, Gateau Basque , chocolate dessert, or add it to the filling of this Pumpkin Tart . I even include it as part of an ice cream  base. You get the idea just how much I enjoy it. If you search crème fraîche  on my blog you’ll find even more recipes.
It’s similar to sour cream and mascarpone but different enough that each should have a place in your cooking repertoire. There are times though when I make too much of this good thing and unfortunately it doesn’t last forever.
This is when I make cultured butter. It’s considered cultured because the lactic acid in the cream ferments slightly creating a tangy, creamy, delightful flavor.
Crème Fraîche is made with just two ingredients. This recipe makes about 8 ounces of butter and a pint of buttermilk.
¼ cup cultured buttermilk, minimally processed and preferably organic
1 quart heavy cream (not ultra pasteurized, no additives, and preferably organic)
Combine the buttermilk and cream in a saucepan and heat to 85°F on an instant read thermometer. Pour into a clean glass, stainless steel, or ceramic bowl. Cover with a couple of layers of cheese cloth or clean cotton towel. Let sit at room temperature (between 65 and 75 degrees F) for 8 to 24 hours, or until thickened. Refrigerate for up to a week.
Salted Cultured Butter
1 batch of crème fraîche from above recipe
½ teaspoon sea salt or to taste
Place the cold crème fraîche in the bowl of a stand mixer. Using the whisk attachment (and covering the entire mixer with food film or a cotton towel to help contain the splattering) whip it until the curds of butter separate from the whey (buttermilk). This can take anywhere from 5 to 1o minutes.
Once the buttermilk has separated from the curds pour the contents of the mixing bowl through a fine mesh sieve saving the buttermilk for cooking or to enjoy as a beverage.
Place the butter curds back in the mixing bowl and pour ice cold water over it. Using a small spatula or wooden spoon press out any remaining buttermilk. Keep pressing and rinsing the butter until the water runs clear.
Mix the sea salt into the butter according to your taste. Form the butter into a log, wrap it in a piece of parchment paper, then plastic wrap and freeze. Let it return to room temperture before you enjoy it on a crusty baguette, ear of corn, or biscuit.