Place the rice in a fine-mesh strainer and rinse under cold water until the water runs clear; set aside. Melt the butter in a medium saucepan over medium heat. Add the onion and garlic, season with salt, and cook, stirring occasionally, until softened, about 5 minutes. Add the rinsed rice and cook, stirring occasionally, until the kernels crackle, about 2 minutes. Add the stock or broth, water, and measured salt and stir to combine. Increase the heat to high and bring to a boil. Reduce the heat to low, cover with a tightfitting lid, and simmer undisturbed until the rice is tender, about 15 minutes. Remove from the heat and let sit covered to steam, about 5 minutes. Fluff with a fork and stir in the parsley. Taste and season with additional salt as needed.