Wild Mushroom Macaroni and Cheese

Kosher Salt
1# Cavatappi pasta
4 Tbsp Butter, plus for baking pan
1/4 C. diced Onion
1 small Garlic clove, minced
1# mixture of Shitake, Portabella, Crimini, sliced thinly
1 Bay Leaf
2 Tbsp. all-purpose Flour
1 1/2 C. Whole Milk
1/4 C. Heavy Whipping Cream
1 tsp. Dijon Mustard
1# grated Extra Sharp White Cheddar
1/2 C. Parmesan Cheese, grated
Paprika, to taste
Salt and Pepper, to taste
1/3 C. Panko Bread Crumbs

Preheat oven to 375 degrees.

Bring a large pot of water to boil.  Add enough salt to water so it tastes like the sea.  Add pasta and cook until pasta is cooked, but firm to the bite (Al dente), about 10 minutes.  Drain, put back in pot and cover with cold water to stop the cooking process, drain and set aside.
Melt all but 1 Tbsp. of butter in a large heavy-bottomed pot over medium high heat.  Add onions and sweat until translucent (approx. 5 mins.), add garlic, cook one more minute.  Add mushrooms and cook until all the water has evaporated and they start turning brown (10-12  mins). 
Add bay leaf and flour, cook another 2 minutes, stirring constantly.  Slowly add the milk, a little at a time, stirring constantly to avoid clumping.  Once all milk is combined, stir in cream.  Turn down heat to medium and simmer for about 3 minutes.
Stir in mustard, cheddar cheese, half of the Parmesan, and paprika, salt and pepper to taste.  Mixture needs to be very flavorful to adjust for pasta.  Simmer for 5 minutes and then set aside.
Butter the bottom of an oven safe baking pan (large enough to hold all the pasta).  Add pasta to mushroom, cheese mixture.  Mix well.  (may need to adjust consistence with small amount of cream).  Transfer mixture to baking pan.  Melt remaining butter and in small bowl pour over breadcrumbs and remaining Parmesan cheese; mix well.  Evenly sprinkle breadcrumb mixture over the pasta.  Put into oven and cook for 35-40 minutes. 
Macaroni and cheese should be bubbling and golden brown on top.  Serve and enjoy.