Heat EVOO, 3 turns of the pan, in skillet or pan with tight fitting lid over medium to medium-high heat. Add onions and garlic and cook to soften 5-6 minutes. Add tomatoes and season with salt and pepper. Then raise heat a bit to medium-high, cover pan and cook to burst the tomatoes, 8-10 minutes, shaking pan occasionally.
Meanwhile, bring a large pot of water to a boil for the pasta. Salt the water and cook pasta to al dente. Heads up: reserve about 1/2 cup starchy water just before draining.
Break up burst tomatoes into chunky sauce then add white beans, parsley and chunks of tuna and heat through. Toss with starchy water and bow ties. Garnish with an extra drizzle of EVOO, lemon juice and zest, then serve.