Mom was raised on a farm in SD. She said that she loved buttermilk when she was a child, but it tasted nothing like our cultured buttermilk. Less tart. As Linda said, you can culture your own by tempering milk with a bit of buttermilk (sort of like you do yogurt, but you don't need to heat it). And if you save the last bit of your homemade buttermilk and continue making more batches, it mellows out a lot. I use store bought buttermilk to make dressings and such, but can't bring myself to drink it. But after a batch or two of my own, I really like the taste.

I just googled coffee cake sour cream buttermilk and a few came up https://www.bakedbyanintrovert.com/cinnamon-sour-cream-coffee-cake/ This one has a buttermilk sauce https://www.countrycleaver.com/2014/04/worlds-best-coffee-cake-buttermilk-sauce.html I'm wondering if you could even take the amt of buttermilk called for and split it half and half with sour cream for any recipe.

Homemade yogurt and buttermilk always reside in my fridge, in a Kumbaya existence. Neither go to waste---or waist---except for Blueberry Buttermilk Ice Cream. Note: This is my adaptation of a recipe shared here. I substituted full-fat buttermilk for the whole milk. Plus, I added 2 cups of fresh blueberries. Blueberry Buttermilk Ice Cream 2 cups fresh blueberries 1 cup granulated sugar 1 Tablespoon finely grated lemon zest 1/4 cup fresh lemon juice 1/8 teaspoon salt 1 cup heavy cream 1 cup full-fat buttermilk In a large saucepan, combine blueberries, sugar, lemon zest and lemon juice. Bring to a boil, then reduce heat to a simmer. Cook until blueberries break down and sugar is dissolved. Allow blueberry mixture to cool slightly, about 10 minutes. Purée mixture in a high-powered blender, or in a food processor, until smooth (if a FP is used, the mixture should be strained). Set aside to cool completely. Add heavy cream and buttermilk to cooled berry mixture (still in the blender), and whirl to combine. Transfer contents to a large bowl. Cover and refrigerate 8 hours, or overnight. Freeze in ice cream maker according to manufacture's directions. Here is the original recipe Sol

Yum! Wish I lived near you :-)