Cook rice: Preheat oven to 450°F with a rack in the upper third. In a small saucepan, combine rice with 1¼ cups water and ½ teaspoon salt. Bring to a boil, then cover and cook over low until rice is tender and liquid is absorbed, about 17 minutes. Remove from heat and keep covered until ready to serve.

Prep ingredients: While rice cooks, trim stems from mushrooms, then thinly slice caps. Remove kale leaves from stems, then cut or tear leaves into large pieces. On a rimmed baking sheet, massage kale with sesame seeds, 1 tablespoon each of neutral oil and water, and a pinch each of salt and pepper.

Sear pork: Pat pork dry, then season all over with salt and pepper. Heat 1 tablespoon neutral oil in a medium skillet over medium-high. Add pork and sear until well browned on all sides, 3–4 minutes per side (pork will not be cooked through). Transfer pork to baking sheet with kale. Reserve skillet and any pan drippings for step 5.

Roast pork & kale: Roast pork and kale on upper oven rack until pork is cooked to an internal temperature of 145°F, and kale is crispy, about 7 minutes. Transfer pork to a cutting board and allow to rest 5 minutes.

Make miso shiitake butter: Meanwhile, heat reserved skillet with pan drippings over medium-high. Add mushrooms; cook, stirring occasionally, until golden-brown, about 3 minutes. Whisk in mirin, sesame oil, 2 tablespoons of the miso, and ½ cup water; bring to a simmer. Cook until sauce is slightly thickened and coats back of a spoon, about 5 minutes. Remove from heat and whisk in 2 tablespoons butter.

Slice pork & serve: Thinly slice pork tenderloin. Fluff rice. Serve pork with crispy sesame kale and rice alongside. Spoon miso shiitake butter over top as desired. Enjoy!