Place the red beans in a bowl and cover with water. Soak overnight.

To cook in a pressure cooker: Drain the red beans and transfer to a pressure cooker; add enough water to cover the beans by 1 inch. Pressure cook on high for 25 minutes, until beans are very tender.To cook on the stovetop: add enough water to a pot to cover the beans by 2 inches and simmer uncovered for at least 1 hour, until beans are very tender.

Drain the red beans from the cooking liquid and transfer to a small pot along with sugar. Cook on medium heat for 5-6 minutes, mashing the beans with a spatula. The sugar should be fully dissolved and the paste will thicken in consistency. Remove from heat. The paste will continue to thicken as it cools.

In a saucepot (ideally at least 3 quarts/3.5L), whisk together all ice cream ingredients including red bean paste. Cook over medium heat and bring the mixture up to 170°F, stirring frequently.

At this stage you have a few options for the texture of the ice cream:A. Traditional. Blend until desired texture, leaving the skins in the base.B. Smooth. Blend until smooth, strain to remove skins.C. Chunky. Stir in ¾ of red bean paste. Swirl the remaining ¼ into the finished quart.

Prepare an ice bath by filling a large container with equal parts ice and water with enough room to place a container containing the ice cream base inside. Pour the ice cream base into a large container set over an ice bath. Chill the mixture until very cold, below 40°F, adding more ice and stirring as needed.

Pour the ice cream base into an ice cream machine and spin according to machine directions. The resulting ice cream should be a smooth, soft-serve consistency. Transfer the ice cream to a storage container and freeze for at least 3 hours to fully firm up.