Boil pasta for 2 minutes, strain, reserving 3/4th a cup of the pasta water, set pasta aside and allow to fully cool and continue to cook

Add the pasta water back into the pot, turning the heat down to medium low. If you have too much water at this point, you can allow it to boil while the temp goes down

Add butter and allow to melt in water

Add half and half and stir

Add in spices and stir

Add in cream cheese and allow to fully melt, stirring occasionally

Let sit for 2 mins, stirring

Add in swiss cheese and stir rapidly until fully melted and not stringy when stirring implement is lifted out of the water

Add in Mexican cheese blend, stirring gently until fully melted as before(turn off the heat now but leave the pot on the stove)

Crush the cracker or ready breadcrumbs as the sauce continues to cook

Add in mustard(skip if used sour cream) and stir until combined

Put pasta in a baking dish(the smaller the better, I used two instant pot sized loaf pans to cook in my toaster oven)

Pour in cheese sauce and tap the container on the counter to let settle

Cover with shredded cheese, followed by breadcrumbs/crackers, and then another layer of cheese

(optional) cover in aluminum foil and cook underneath a baking tray so if it drips it's less messy to clean up

Bake at 375 degrees(if foiled) or 350(if not foiled) for 10 minutes