Preheat oven to 375ºF.
Heat EVOO in a skillet over medium to medium-high heat; add butter and melt into oil. Add onions and garlic, and season with salt and pepper. Add flour and stir 1 minute. Whisk in wine then gravy or stock and milk; adjust salt and pepper, and season with nutmeg to taste. Let thicken enough to coat a spoon and stir in parm cheese.
Stir turkey, cauliflower, peas, pasta into the sauce and turn everything into a casserole dish. Top with breadcrumbs and bake until heated through, about 30 minutes.