Bring a large pot of salted water to a boil. Meanwhile, cook the pancetta in a large nonstick skillet over medium-high heat, turning, until browned and crisp, 8 to 10 minutes. Remove to a paper towel–lined plate and wipe out the skillet.
Add the ravioli to the boiling water and cook as the label directs. Reserve 1/2 cup cooking water, then drain gently.
Combine the butter and lemon zest and juice in the reserved skillet over medium heat. Add the peas, ravioli and 1/4 cup of the reserved cooking water; toss to coat. Stir in the pecorino and toss. Season with salt and pepper. Add more cooking water, 1 tablespoon at a time, to loosen.
Divide the ravioli, peas and any sauce among shallow bowls. Sprinkle with more pecorino. Crumble the pancetta and scatter over the ravioli. Top with basil.