Bring a few inches of water to a low boil in a skillet. Add salt and beans, and cook 3-4 minutes to tender-crisp, drain.
Heat EVOO and butter in a large, deep skillet over medium to medium-high heat. Add mushrooms and lightly brown them, 7-8 minutes. Add shallots and garlic, and season with salt, pepper and thyme. Stir 2-3 minutes more, add flour, stir a minute then add wine. Stir in stock and thicken. Add cream and reduce heat to simmer. Add cheese, beans and chicken, and thicken a bit.
Transfer into a casserole dish and cool. Cover and refrigerate. To cook, bring back to room temp and bake at 375°F until bubbly, about 50-60 minutes. Top with homemade* or store-bought fried onions.