Bring medium pot with water to a boil and cook penne according to instructions on the box. Once cooked, drain the pasta and set aside to cool.
Bring small sauce pan with water to a boil. Add salt and peas to the pan and boil for 2-3 minutes. Drain the peas and set aside to cool.
Heat large skillet over medium-low heat and add marinara sauce. Once marinara sauce is heated, turn heat to low and add smoked salmon to the skillet. Break apart smoked salmon slices with a wooden spoon or silicone spatula into small chunks and mix well with the sauce.
Add butter, heavy cream or half and half, grated cheese to the skillet and stir to combine.
Toss in penne pasta, peas and gently combine with pasta sauce. Do not overcook pasta and peas.
Transfer pasta to a large serving dish and garnish with fresh dill and lemon zest.