One tasty app!

4 shallots (peeled, half chopped, half thinly sliced, divided)
1 1/2 cups buttermilk
1 cup flour (plus 2 tablespoons)
1/2 teaspoon cayenne
vegetable oil (for frying)
1 1/2 pound green beans (trimmed, cut in 1-inch pieces)
3 tablespoons unsalted butter
2 garlic cloves (peeled, thinly sliced)
1 cup chicken stock
1 cup half & half
2 cups Parmigiano-Reggiano (grated)
Kosher salt and freshly ground black pepper (to taste)

For the Fried Shallots: In a large Dutch oven heat 2-3 -inches of vegetable oil for frying. Line a plate with paper towels.
In a medium bowl, add the thinly sliced shallots and cover with buttermilk. Toss the shallots to separate pieces and completely coat.
In another bowl or shallow dish, whisk together 1 cup of flour and cayenne just until combined.
Remove some shallots from the buttermilk and dredge in the seasoned flour mixture. Shake off any excess flour and gently place in the heated oil. Fry until golden and crispy, about 1 minute. Using a heatproof slotted spoon, remove the shallots to a paper towel-lined plate. Season with salt to taste. Fry remaining shallots in batches.
For the Casserole: Preheat oven to 375ºF.
Bring a large pot of water to a boil and season with salt.
Prepare a large bowl with water and ice, fitted with a strainer inside the bowl.
Cook the green beans in the seasoned water for 1 minute then remove and immediately plunge into the ice bath. Allow beans to cool then remove to a paper towel-lined plate to dry.
While the beans are cooling and drying, heat a saute pan over medium heat, and melt the butter. Add the chopped shallots and season with salt. Cook until soft, about 3 minutes, then add garlic and cook just until fragrant.
Sprinkle the 2 tablespoons of flour into the pan and stir to coat shallots and garlic. Slowly whisk in the chicken stock, whisking out any lumps. Whisk in the half & half and season to taste. Simmer for 2 minutes or just until thickened. Stir in cheese and remove from heat.
Toss the beans and cooked shallot, garlic mixture with the cheese sauce. Pour into a 9×9 casserole dish and bake for 20-25 minutes. Liquid should reduce and thicken.
Remove from oven and top with crispy shallots. Cool slightly, about 5 minutes, and serve.
Tip: Your toaster oven may cook faster than your regular oven, so you may have to lower the temperature of your toaster oven before you begin cooking!