Heat oil in Dutch oven over medium heat until shimmering.
Add pancetta and cook, stirring occasionally, until beginning to brown, 3 to 5 minutes.
Add onion, carrot, celery, ½ teaspoon salt, and ¼ teaspoon pepper and cook, stirring occasionally, until vegetables are softened, 5 to 7 minutes.
Add garlic and cook until fragrant, 30 seconds.
Add rice and salami and cook, stirring frequently, until rice grains are translucent around edges, about 3 minutes.
Stir in tomato paste and cook until fragrant, about 1 minute.
Add wine and cook, stirring constantly, until fully absorbed, 2 to 3 minutes.
Stir in broth, reduce heat to medium-low, cover, and simmer for 10 minutes, stirring halfway through simmering.
Stir in cabbage and continue to cook, covered, until almost all liquid has been absorbed and rice is just al dente, 6 to 9 minutes longer.
Add beans and hot water and stir gently and constantly until risotto is creamy, about 3 minutes.
Remove from heat, cover, and let stand for 5 minutes.
Stir in Parmesan and butter.
If desired, add up to 1 cup extra hot water to create fluid, pourable consistency.
Stir in vinegar and season with salt and pepper to taste.
Sprinkle with parsley and serve immediately, passing extra Parmesan separately.
