Grate your cheese, chop your potatoes, and tear up your cabbage.
Bring a large pot of water to a boil and add salt, potatoes, and cabbage.
Your potatoes will need about 14 minutes to be fully cooked. Refer to the package instructions on your penne and add the penne to the same pot so that the potatoes and pasta will be finished cooking at the same time. (For example, if the box provides for a 12-minute cooking time, add your pasta to the pot 2 minutes after adding the potatoes and cabbage).
While the pasta and vegetables are cooking, add the butter and garlic to a small pan over medium-low heat. Once the butter has completely melted, reduce the heat to the lowest possible setting. The garlic will eventually turn a toasted golden color.
When the pasta is cooked, drain the excess liquid completely. Add half the pasta, cabbage, potatoes to a casserole dish and then sprinkle with half the cheese.
Add the remaining half of the pasta, cabbage, and potatoes to the casserole dish. Sprinkle with the rest of the cheese.
Pour the butter and garlic over the top of the cheese.