Cook pasta according to package directions until al dente. Drain and set aside.
Heat olive oil in a large, heavy-bottomed pot or skillet over medium-high heat. Add the sausage and broccoli, and saute for 7-8 minutes or until the sausage just starts to brown and the broccoli is bright green and crisp-tender. Add in the garlic and cook 1 more minute.
While the sausage and broccoli are cooking, stir together the mascarpone cheese, lemon zest and juice, lots of freshly ground pepper and a pinch of salt.
When sausage and broccoli are done, add the pasta, cherry tomatoes, and mascarpone mixture to the pan and stir to combine, allowing tomatoes to just heat through and the cheese to melt, coating everything. Taste for seasoning, adding more salt or pepper as needed. Serve warm.