Roasted-Buckwheat Custards

Ingredients

• 12 ounces heavy cream , plus more as needed
• 1 1/2 ounces soba-cha, or roasted-buckwheat tea , plus more for garnish
• Pinch kosher salt
• 6 large egg yolks
• 3 ounces sugar
• Whipped cream, for garnish

Directions

1. Heat the oven to 300 degrees F (150 degrees C), and put a kettle on to boil. Combine the cream and soba-cha in a medium saucier or saucepan. Set it over medium heat and warm it only to the faintest simmer, using a rubber or silicone spatula to stir often and sweep along the base and sides so the dairy does not scorch. Take the pan off the heat and steep the mixture for 5 minutes.
2. Pour the steeped cream through a fine strainer into a heatproof measuring cup, pressing the soba-cha firmly to get out as much liquid as you can. Throw away the spent soba-cha. Add fresh cream as needed until the infused cream measures 1 1/2 cups total. Stir in a scant pinch of salt.
3. In a clean medium saucier or saucepan, or in the first pan once it is cool enough that the yolks will not scramble, whisk together the egg yolks and sugar. Slowly pour in the hot infused cream, whisking the whole time. Place the pan over medium-low heat and cook, constantly stirring and running a rubber or silicone spatula along the pot's bottom and sides, until an instant-read thermometer reads 140 degrees F (60 degrees C). Take it off the heat.
4. Strain the custard through a fine sieve, divide it among the ramekins, and arrange the ramekins in a baking dish. Drape the baking dish with aluminum foil but leave a small gap open, then move it to the oven. Carefully pour in the prepared boiling water, avoiding the ramekins, until it reaches about 3/4 of the way up their sides. Close the foil opening and bake until the custards are barely set, 30 to 45 minutes.
5. Lift the baking dish from the oven carefully so the water stays steady, then leave the custards to cool in the water bath for about 1 hour. Take the ramekins out of the water bath, cover them with plastic, and refrigerate until completely cold, at least 3 hours.
6. The custards can stay refrigerated for up to 5 days. When you serve them, add whipped cream on top and finish with a few roasted buckwheat seeds scattered over each one.