Start by boiling your penne pasta in salted water until just al dente. I like cooking it slightly under, so it finishes perfectly in the oven. Drain and set aside.
In a skillet, melt butter and sauté minced garlic until fragrant. Then whisk in flour to create a roux, slowly add milk and cream, and stir until smooth. Finish with Parmesan, mozzarella, Italian seasoning, salt, and pepper.
Add the drained pasta to the sauce and mix until fully coated. If you’re adding cooked chicken or vegetables, fold them in now for an even distribution.
Transfer the pasta mixture into a greased baking dish and sprinkle extra mozzarella on top. Bake at 180°C (350°F) for 20-25 minutes until the cheese is golden and bubbly.
Remove from the oven, let it cool for a few minutes, and serve immediately. Garnish with fresh parsley if you like, for an extra pop of color.