In a large pan, melt the butter on a low flame.
Add the garlic and shallow fry until the garlic starts browning.
Add in cream cheese, stir and melt.
Slowly add milk and whisk, to remove lumps.
Now finally add the parmesan cheese and stir until a smooth sauce begins to form.
In case you want to add peas, you can do that now so that the peas can soften a little.
Cook until the sauce thickens. Then turn off the flame and mix the sauce with the pasta to serve.