Chop mushrooms into 1 inch squares and cook in well-oiled skillet at medium-high heat for 5 minutes until browned
Remove mushrooms from skillet and add 1/2 cup chopped onion, 2 minced garlic cloves and 2 Tbsp flour to skillet. Cook for around 7 minutes until onions are soft.
Add 2 cups of whole milk and 1/4 cup dry white wine to skillet. Bring to boil then simmer for 5 minutes
Add 1/2 cup grated Parmesan cheese and 1 cup of peas, cook 2 minutes, stirring frequently.
Combine sauce with cooked mushrooms and rigatoni pasta.
Serve with grated lemon zest on top!