While preparing the puttanesca, make pasta (or polenta) in a separate pot
Cut about 2/3 of tomatoes in half. Leave the rest whole
Heat a medium sized skillet over medium low heat
Add diced pancetta and allow to cook slowly until crispy and fat is rendered
Remove pancetta and set aside on a paper towel covered plate
Add olive oil and turn heat up to medium high
Add the garlic and onions to the pan and cook stirring occasionally until softened, about 4 - 5 mins
Add cherry tomatoes to the pan and toss to combine with onions and garlic
Cook until tomatoes are softened and beginning to give up their juices
Add red wine, scrape bottom of pan to release any browned bits, and bring to a simmer
Cook until liquids reduce by about half
Add the pesto and stir to combine into tomato mixture
Lower heat and add capers. Cook for about 1 min, stirring frequently
Add olives and reserved pancetta and stir to combine. Cook for 1 more min until everything is heated through
Remove from heat. Add salt and pepper to taste
Serve over prepared pasta (or polenta) and top with Pecorino