Buttermilk Ice Cream Recipe

Prepare custard base

Combine whole milk, heavy cream, and half the sugar (1/2 cup) in a medium saucepan. Split the vanilla bean lengthwise, scrape seeds into the milk mixture and add the pod (or add vanilla extract later). Heat over medium until mixture is steaming and small bubbles form at the edges, about 6–8 minutes; do not boil.

Whisk yolks and sugar

While the milk heats, whisk the egg yolks with the remaining 1/2 cup granulated sugar in a heatproof bowl until pale and slightly thickened, about 1–2 minutes.

Temper eggs

Slowly ladle about 1/3 cup of the hot milk mixture into the yolks while whisking constantly to temper. Repeat with another 1/3 cup. Then slowly whisk the tempered yolk mixture back into the saucepan with the remaining milk mixture, stirring constantly.

Cook to custard

Return the pan to low–medium heat and cook, stirring constantly with a wooden spoon or heatproof spatula and scraping the bottom, until the custard thickens enough to coat the back of the spoon (temperature about 170–175°F / 77–80°C), about 4–7 minutes. Do not allow it to boil.

Strain and cool

Remove from heat. Strain the custard through a fine-mesh sieve into a bowl to remove the vanilla pod and any coagulated bits. Stir in the salt. Cover the surface with plastic wrap to prevent a skin from forming and cool to room temperature, about 20–30 minutes.

Add buttermilk

When the custard is cool, whisk in the buttermilk and (if using) the vanilla extract instead of bean. If you used a vanilla bean earlier, you may omit extra extract. Add lemon zest here if using. Taste and adjust salt/sweetness; buttermilk has tang, so you may prefer a touch more sugar if desired (add up to 1–2 tbs if needed).

Chill thoroughly

Cover and refrigerate the mixture until very cold, at least 4 hours or preferably overnight. For quicker chills, place the bowl in an ice bath after straining and then refrigerate.

Churn

Once thoroughly chilled, churn the mixture in an ice cream maker according to the manufacturer's instructions until it reaches a soft-serve consistency, typically 20–30 minutes.

Finish and freeze

Transfer churned ice cream to an airtight container, smooth the top, and press a piece of plastic wrap directly onto the surface to minimize ice crystals. Freeze until firm, at least 4 hours.

If you like, swirl in honey or fold in mix-ins (candied citrus, toasted nuts, or shortbread pieces) just before transferring to the container. For a bright note, fold in the lemon zest when adding the buttermilk so the flavor distributes evenly.

When ready to serve, let the ice cream sit at room temperature for 5–10 minutes to soften slightly for easy scooping. Drizzle with a little honey if desired.