Step 1Unroll the pancetta and cut it into pieces about one-half-inch long. Heat the olive oil in a large saut? pan over medium-high heat. When the oil is hot, add the pancetta and cook until the meat is well-browned and has rendered much of its fat, about 8 minutes.
Step 2Pour off all but about 2 tablespoons of the fat, return the pan to the heat and add the onions. Cook until the onions are tender, about 3 minutes. Add the garlic and the Romano beans and stir them with the onions and pancetta. Add the salt and three-fourths cup water and reduce the heat to medium.
Step 3Cover and cook, stirring occasionally, until the beans are silky in texture and extremely flavorful, about 45 minutes. If the mixture begins to cook dry, add a little more water.
Step 4When the beans are cooked, remove the lid and cook long enough to evaporate most of the remaining water, about 5 minutes.
Step 5Reduce the heat to low and add the cherry tomatoes. Cook until they are warmed through. Serve either warm or at room temperature, first stirring in the basil and tasting and correcting the seasoning.