Wash beans.

Place beans, sugar, lemon juice and water into a saucepan.

Place saucepan over medium high heat and bring to boil. Boil uncovered for 3 minutes.

Decrease heat to low. Cover pan and cook simmer until beans are very tender, adding additional water as needed, about 2 1/2 to 3 hours.

When done, there should be a total of 3 cups beans and liquid. Adjust the liquid by adding more water or draining off some of the liquid to leave 3 cups total mixture.

Let mixture cool 5 minutes.

Strain the bean mixture through a sieve. Discard bean skins left in the sieve.

Store the bean mixture, covered, in the refrigerator 2 to 3 hours until cold.

Place a saucepan over medium heat.

Add milk and cream. Bring up to a simmer. Adjust heat as needed.

In a small bowl, combine egg yolks and sugar, stirring with a wire whisk until well mixed.

Stir 1/4 cup of the hot cream/milk mixture into the egg/sugar mixture. Mix well.

Pour egg/sugar mixture into milk/cream mixture in the saucepan.

Place the saucepan over low heat. Cook and stir until mixture thickens a bit, about 5 minutes.

Remove from heat. Add vanilla.

Place, covered, in the refrigerator, 2 to 3 hours until cold.

When ready to make ice cream, combine bean mixture and custard mixture.

Place in your ice cream maker and process according manufacturers instructions. Enjoy cold.