Bottomless Soft Swirl Tub Recipe

Split and steep vanilla

Split the vanilla bean lengthwise and scrape the seeds into a medium saucepan. Add the scraped pod to the pan as well.

Combine dairy and dry solids

Pour 6 cups whole milk (preferably from Jersey cows) and 2 cups heavy cream into the saucepan with the vanilla. Add 1 cup granulated sugar, 1 cup powdered milk (optional for body), 1/4 cup nonfat dried milk (optional), 2 tablespoons corn syrup and 1/4 teaspoon salt. Whisk to combine.

Heat the mixture

Warm the mixture over medium heat, stirring frequently, until it reaches 170–175°F (77–80°C) and steam rises. Do not boil. This step dissolves the sugars and hydrates the powdered milk.

Tempering egg yolks (optional custard base)

If using egg yolks for a custard-style base (richer mouthfeel), whisk 4 egg yolks in a bowl. Slowly add 1 cup of the hot milk mixture into the yolks while whisking constantly to temper. Then return the tempered yolk mixture to the saucepan and cook gently, stirring constantly, until the mixture reaches 175–180°F (79–82°C) and coats the back of a spoon. Do not let it boil.

Add stabilizer and finish heating

If using xanthan gum or a commercial stabilizer, sprinkle it in now and whisk vigorously to hydrate (or follow the stabilizer manufacturer's instructions). Remove the saucepan from heat. If you used a vanilla pod, remove and discard the pod. Stir in 2 teaspoons pure vanilla extract and the 2 tablespoons corn syrup (if not already added).

Cool the base quickly

Strain the mixture through a fine-mesh sieve into a clean container to remove any cooked bits. Chill the base rapidly to 40°F (4°C) or below — place the container in an ice bath, stirring occasionally, then refrigerate for at least 4 hours or overnight to fully age the mix (improves texture).

Prepare machine

Sanitize and set up your soft-serve machine or batch freezer according to manufacturer instructions. Ensure the machine and the serving tub are chilled/sanitized so the product remains safe during service.

Process the mix

Pour the chilled base into the soft-serve machine's hopper and churn according to the machine's directions until you have a smooth, soft-serve consistency (target draw temperature about 18–22°F / -8 to -6°C depending on equipment). If using a home ice-cream maker, churn to a soft-serve stage then keep the churned product in a blast chiller or freezer to maintain consistency for serving.

Fill the tub

Transfer the soft-serve directly into the chilled insulated tub. Smooth the surface with a sanitized paddle. Keep the tub at 10–15°F (-12 to -9°C) if possible for best texture during service; if that's not feasible, keep it as cold as possible and replenish frequently from the machine.

Maintain bottomless service

Keep a schedule for refilling: refill from the machine frequently to maintain swirl texture and food safety. Store backup mix chilled (below 40°F / 4°C) and re-churn small batches as needed. Sanitize utensils and the tub lip between refills.

Portion and garnish (optional)

Serve using a soft-serve nozzle or by spading scoops from the tub. Offer garnishes such as hot fudge, caramel, crushed cookies, or fruit separately so guests can customize. Keep garnishes in proper cold/hot holding as applicable.

Food safety and holding time

Do not hold soft-serve in the serving tub for extended periods at temperatures above safe cold-holding levels. Discard product held too long (follow local health code). Keep the base refrigerated and the machine clean to prevent bacterial growth. Rotate and sanitize frequently during service.

After service, purge and clean the machine according to manufacturer instructions. Wash and sanitize the serving tub and utensils. Proper cleaning ensures consistent product and safe bottomless operation.