Add your peppercorns to a skillet and heat on medium low. Toast for 2-3 minutes, then remove from heat.
Crush the peppercorns with a mortar and pestle, or, if you don't have one, use the bottom of the pan you used. Crush them on a cutting board. Set them aside.
Now, cook the pasta according to package directions, drain when they are al dente.
When the pasta is done, make the cheese sauce.
In a large skillet that will fit the pasta in, heat the vegan butter on medium high.
Once the butter has melted, add the flour and whisk to fully combine and make a roux(paste). Let simmer for about 1 minute.
Then, pour the non-dairy milk into the skillet and whisk with the roux, making sure it is fully combined and there are no lumps of the roux left.
Bring to a simmer, reduce heat to medium low and let simmer for 1-2 minutes, or until the sauce starts to get thick. Season with a few pinches of salt.
Add the vegan mozzarella, vegan Parmesan and a few large pinches of the crushed peppercorns.
Whisk to combine and continue to simmer until the cheeses have melted into the sauce and the sauce is completely smooth.
Taste and adjust seasonings, adding more salt or crushed pepper to the sauce.
Pour the cooked pasta into the skillet with the cheese sauce and toss to coat the pasta in the sauce. Let heat for a minute to make sure the pasta is nice and hot again.
Serve immediately with extra crushed pepper on top if desired. I love to serve it with roasted broccoli as well.