Step 1

Add the yolks to a medium bowl and set the bowl next to the stove, along with a whisk and a ladle.

Step 2

In a medium saucepan, combine the half and half, heavy cream, salt, allulose, and vanilla bean. Heat the mixture over medium-low heat to scalding (roughly 170 degrees F - giving off steam, but not quite simmering), stirring regularly.

Step 3

Once all of the allulose has dissolved in the cream mixture and it's reached scalding, turn off the burner. Now gradually whisk two ladlefuls of the hot cream mixture into the yolks. Don't worry, it's easy! Just make sure you're whisking the entire time and everything will be fine.

Step 4

Whisk the tempered yolk mixture into the saucepan of hot cream. Turn the burner back on to medium-low heat and cook the mixture, stirring regularly, until it returns to 170° F and thickens noticeably to coat the back of a spoon. When this happens the yolks will be cooked.

Step 5

Remove the saucepan from the heat and stir in the vanilla extract.

Step 6

Strain the keto vanilla ice cream mixture through a fine mesh sieve and into a clean container set in an ice bath. Chill the ice cream mixture until completely cold, stirring occasionally. If you try to churn the mix when it's room temperature it'll take much longer to freeze, and the texture won't be as nice.

Step 7

Churn the keto vanilla ice cream mixture in your ice cream machine following the manufacturer's instructions. When it's finished churning it should have roughly the consistency of soft serve (it'll firm up to be the perfect scoopable ice cream consistency after a few hours in the freezer). Transfer the churned ice cream to your storage containers and store in the freezer.