Creating Baked Japanese Sweet Potato with Tonka Vanilla Ice Cream is easy if you follow these simple steps:

Prepare the Baked Japanese Sweet Potatoes

1. Preheat your oven to 400°F (200°C).
2. Wash the Japanese sweet potatoes thoroughly under running water to remove any dirt.
3. Pat Dry the sweet potatoes with a paper towel to ensure they are completely dry.
4. Pierce each sweet potato a few times with a fork to allow steam to escape during baking.
5. Brush the sweet potatoes lightly with olive oil and sprinkle sea salt over them.
6. Place the sweet potatoes on a baking sheet lined with parchment paper.
7. Bake in the preheated oven for about 45 minutes or until they are tender and can be easily pierced with a fork.

Prepare the Tonka Vanilla Ice Cream

1. Heat the heavy cream, milk, and sugar in a saucepan over medium heat until it starts to simmer. Stir to dissolve the sugar.
2. Remove from heat and add the grated tonka bean and vanilla extract. Let it steep for about 30 minutes.
3. In a separate bowl, whisk the egg yolks until smooth.
4. Slowly pour the warm cream mixture into the egg yolks, whisking constantly to temper the eggs.
5. Return the mixture to the saucepan and cook on low heat, stirring frequently until it thickens enough to coat the back of a spoon (about 5-7 minutes).
6. Strain the mixture through a fine mesh sieve into a bowl to remove any solids.
7. Chill the mixture in the refrigerator for at least 2-3 hours or until completely cold.
8. Churn the chilled mixture in an ice cream maker according to the manufacturer's instructions.
9. Transfer the churned ice cream to a container and freeze for at least 4-6 hours or until firm.