IF IT’S EVER discovered that cultured buttermilk is bad for humans, I am doomed. Until 2015, I was content with substituting milk soured with lemon juice in my baking. Then Grace Harbor Farms, in Custer, Whatcom County, introduced its outstanding cultured buttermilk. I now use it so routinely, it goes on the shopping list as automatically as coffee.

Cultured buttermilk provides abundant lactic acid, and that acidity does all sorts of useful things in cooking. It creates tenderizing effects by breaking down protein in meat or gluten when used in marinades or baking. It activates leavening in baking soda. It wakes up your palate, just like sprinkling lemon juice on a dish before serving makes other flavors pop. Unlike most acidic ingredients, it adds creaminess, creating Meryl Streep-like versatility in dips, salad dressings and smoothies.

Grace Harbor’s buttermilk is closer to butter than it is to milk. Even after extended shaking to mix it before using, I run a spoon around the bottle’s top to extract the custard-thick cultured cream. Its flavor compared to all other brands I’ve tried is like fresh-squeezed lemonade compared to concentrate. They’re related, but one is better across the board, from color and fragrance to flavor complexity and texture.

Where to Buy this Buttermilk

Find Grace Harbor Farms buttermilk at Central Market; PCC Community Markets; Beacon Hill Red Apple; Town & Country Markets; fullcircle.com delivery boxes; and many Haggen, Whole Foods Markets and QFC stores.

Buttermilk has strong associations with Southern cooking, from fried chicken to biscuits and caramel cake. In fact, Belinda Smith-Sullivan’s new book, “Southern Sugar,” includes a dozen recipes with it. She wants people to know buttermilk’s history. “Real buttermilk is made by churning whole milk or cream. The liquid that remains is ‘pure’ buttermilk. Freshly churned buttermilk is sour. Commercial buttermilk in supermarkets is made by adding lactic acid bacteria to pasteurized milk. This produces a thicker consistency buttermilk that is tangy. Modern recipes are developed for use with commercial buttermilk. If someone is lucky enough to get their hands on ‘pure’ buttermilk, start with half the amount called for in the recipe, and add more as appropriate for consistency.”


I used Grace Harbor buttermilk for the caramel frosting and the cake, with wonderful results: tender cake layers, and creamy, penuche-like frosting. The frosting needs a little patience but is absolutely worth it.

Caramel Cake
12 to 16 servings

For the cake:
1 cup unsalted butter, room temperature
2 cups sugar
4 large eggs, room temperature
3 cups self-rising flour
1 cup buttermilk, room temperature
2 teaspoons vanilla extract

For the frosting:
1 cup sugar
1 cup packed light brown sugar
1 cup buttermilk, room temperature
1 cup unsalted butter, room temperature
1 teaspoon baking soda

1. Preheat oven to 350° F. Spray 3 (9-inch) cake pans with nonstick spray, and line with parchment paper.

2. In the bowl of a stand mixer, cream butter on medium-high speed until fluffy and pale yellow. Add sugar and cream another 3 minutes. Add eggs, 1 at a time, and beat well after each. Lower speed, and add flour and buttermilk alternately, beginning and ending with flour. Add vanilla and beat well; divide evenly between the 3 pans.

3. Bake 25-30 minutes, until a cake tester comes out clean. Transfer to wire rack, and let cool in the pan for 10 minutes. Invert the layers onto wire racks; remove parchment paper, and let cool completely before starting the caramel frosting.

4. In a large heavy-bottom saucepan or cast-iron Dutch oven, mix all frosting ingredients over medium heat. Cook, stirring occasionally, until mixture comes to a boil. (Watch very carefully, as it tends to bubble up — do not walk away from this process!) Cook to 235° F on a candy thermometer. If you do not have a candy thermometer, cook 10-12 minutes, until mixture is thick enough to coat the back of a spoon. Remove from heat, and, using a wooden spoon, beat until creamy and ready to spread.

5. Working very quickly before the frosting starts to harden, place a rack inside a sheet pan lined with parchment paper. Invert 1 cake layer onto a cardboard cake round covered in foil, and place on rack. Spread some of the caramel frosting on top. Repeat with second cake layer. Finally, remove parchment from third layer, and place on top. Pour more frosting on top, and spread the remainder on the sides. If the frosting starts to harden, warm over low heat until spreadable again. To smooth out the frosting, dip the spreading spatula in very hot water as necessary and continue frosting.
©2021 by Belinda Smith-Sullivan. Excerpted from “Southern Sugar” by permission of Gibbs Smith.