Step 1

In a medium saucepan, stir heavy cream, milk, and salt over medium heat until it starts to simmer. Remove from heat.

Step 2

In a medium bowl, whisk the egg yolks and sugar until thick and pale.

Step 3

While whisking egg yolk mixture constantly, gradually add the hot cream mixture. Return to saucepan to low heat. Stir the mixture slowly, but constantly, scraping the bottom and sides of the pot until the base is thick enough to coat the back of a spoon. Remove from heat. (Do not let the mixture boil or you will end up with egg curdles)

Step 4

Let the mixture cool completely. Add vanilla extract and stir until well combined.

Step 5

Blend together half of the red bean paste and 1/4 cup of ice cream base with food processor until smooth. Transfer the mixture back to the ice cream base and mix until well combined.

Step 6

Cover the mixture and refrigerate for at least 4 hours or up to overnight.

Step 7

Process the ice cream base in an ice cream maker according to manufacturer's instructions. During the last 5 minutes of the churning, add the remaining red bean paste.

Step 8

Transfer the churned ice cream to a freezer container. Freeze for least 4 hours before serving.