Spring is in full bloom in New York, and so is Padma Lakshmi’s career. “I was passing by Central Park, and all these beautiful flowers, magnolias, cherry blossoms, were in bloom,” says the glamorous host of “America’s Culinary Cup,” whose finale airs next week. Over Zoom, she reflects on the triumph of making a show that was truly hers — and the glittery pieces she wore while filming it.