Rinse the rice: Put the rice in a fine-mesh sieve and set it over a medium saucepan. Slowly pour the water over the rice, gently swishing with a spatula, and collecting the starchy liquid in the saucepan below. Once drained, lift off the sieve and set aside. Season the starchy liquid with 2 teaspoons kosher salt and bring to a simmer over high heat. Cover and reduce the heat to low to keep warm.

Char the lemons: In a medium Dutch oven, heat the oil over medium heat until shimmering. Cut the lemons in half and place them cut-side down in the oil. Cook, undisturbed, until deeply charred (blackened bits will speckle the oil, that’s just what you want), 6 to 8 minutes. Flip and lightly sear the lemon rinds to flavor the oil, about 1 minute. Transfer the lemons to a cutting board to cool.

Toast the rice: Add the drained rice and pepper to the Dutch oven and stir to coat with the oil. Cook, stirring constantly, until the rice looks dry, smells toasty, and sizzles and pops, 3 to 5 minutes.

Simmer: Reduce the heat to medium-low and add enough of the warm starchy water to barely cover the rice. Cook, stirring frequently, until most of the liquid has been absorbed. Add the rest of the water in stages, each time adding enough to barely cover and stirring until absorbed before adding more.

Cook, stirring frequently, until the rice is almost tender but with a raw bite left at the core, and the water is thickened into a starchy sauce that generously immerses the rice. (If you’ve used up all the water before the rice is cooked, or need more starchy sauce, add hot tap water as needed. Err on the side of too loose, as the risotto will thicken as it cools.) Depending on the type of rice, this will take between 14 and 19 minutes.

Enrich the risotto: Add the Parmesan and stir vigorously until mostly melted. Add the butter and continue stirring until creamy and emulsified. Remove from the heat. Squeeze the charred lemons into the risotto through a fine-mesh sieve, pressing to push through any tender pulp; discard the rinds. Taste and add salt if needed. Serve right away.