Bring a large pot of salted water to a rolling boil for the pasta.
Meanwhile, heat the olive oil in a large non-stick skillet over medium heat.
Add the crushed garlic and crushed red pepper flakes to the skillet and cook, stirring occasionally, until the garlic is fragrant and lightly browned, about 2–3 minutes.
Stir in the chopped canned whole tomatoes and reduce the heat to medium-low; simmer for about 10 minutes.
Add the fresh cherry tomatoes and simmer for an additional 10 minutes, until they begin to soften.
Stir in the drained cannellini beans and return the sauce to a gentle simmer; season with sea salt to taste and keep the sauce warm over low heat.
Cook the whole grain penne in the boiling water according to package directions until al dente, being careful not to overcook.
Drain the pasta and transfer it to a large bowl.
Add the hot tomato-bean sauce and the baby arugula to the pasta and toss with a large spoon until the arugula wilts and everything is well combined.
Divide the pasta among warm bowls and top with grated parmesan, if desired.