A chef using a cooking torch on a dessert at Refettorio Gastromotiva RIO DE JANEIRO — Consider what it takes to keep all those Olympian machines nourished and hydrated for one meal at the Rio Games: 250 tons of raw ingredients to fill the bellies of 18,000 athletes, coaches and officials in the Olympic Village. Now multiply that figure by three — for breakfast, lunch and dinner — and again for each day of the Games. On the other side of the Atlantic Ocean, the Italian chef Massimo Bottura also did the math and was inspired, not by the tantalizing dimensions of herculean consumption but by the prospect of colossal waste. “I thought, this is an opportunity to do something that can make a difference,” said Mr. Bottura, 53, a fast-talking blur of a man whose restaurant in Modena, Osteria Francescana, recently earned the top award from the World’s 50 Best Restaurants. On Thursday night, that something looked like this: In a fraying section of downtown