Instructions

• STEP 1

  FOR THE HOMEMADE CRISPY ONIONS: Preheat oven to 375°F. Coat a baking sheet pan with oil and set aside.

  • 1 tsp extra virgin olive oil

• STEP 2

  Peel, halve, and quarter onion lengthwise. Thinly slice crosswise and place in a small bowl. Drizzle with buttermilk, toss to coat, and set aside to tenderize, about 5 minutes.

  • 1/2 medium yellow onion
  • 1/4 cup buttermilk

• STEP 3

  Meanwhile, place flour and spices in a medium bowl. Stir to combine.

  • 1/3 cup all-purpose flour
  • 1/4 tsp onion powder
  • 1/4 tsp salt
  • 1/8 tsp black pepper

• STEP 4

  Transfer onions to the bowl with the flour, squeezing them of any excess buttermilk. Using your hands, toss onions in flour mixture to coat.

• STEP 5

  Transfer coated onions to the baking sheet, spreading them out in an even layer. Drizzle onions with additional oil.

  • 1 tbsp extra virgin olive oil

• STEP 6

  Place onions in the oven and bake, flipping every 6-7 minutes, until crispy and golden brown, 20-25 minutes. Remove from oven and let cool on the baking sheet. (Keep the oven turned on.)

• STEP 7

  FOR THE GREEN BEAN CASSEROLE: While the onions are baking, wash and dry the fresh produce.

  • 1 1/2 lbs green beans
  • 1 lb cremini mushrooms
  • 1 small pkg fresh thyme

• STEP 8

  Fill a large pot halfway with hot water (from the tap), cover, and bring to a boil.

• STEP 9

  Meanwhile, trim and cut green beans crosswise into thirds.

• STEP 10

  Once the water is boiling, uncover the pot, add salt and green beans, and stir for a few seconds. Cook, stirring occasionally, until just tender, 2-3 minutes. Drain and rinse under cold water to cool; transfer to a large baking dish and spread out in an even layer.

  • 1 tbsp salt

• STEP 11

  Meanwhile, trim and thinly slice mushrooms.

• STEP 12

  Preheat a large skillet over medium-high heat.

• STEP 13

  Once the skillet is hot, add butter and swirl to coat the bottom. Add mushrooms and cook, stirring occasionally, until tender and golden, 6-7 minutes.

  • 2 tbsp butter, unsalted

• STEP 14

  Meanwhile, slide thyme leaves off the stems; discard stems.

• STEP 15

  When the mushrooms are done, add thyme and salt to the skillet. Stir to combine and transfer to the baking dish with the green beans. (Reserve skillet for the next step.)

  • 3/4 tsp salt

• STEP 16

  Return skillet to medium heat. Once the skillet is hot, add more butter and swirl to coat the bottom. Add flour and whisk until smooth. Cook, whisking frequently, for 1 minute.

  • 3 tbsp butter, unsalted
  • 3 tbsp all-purpose flour

• STEP 17

  Slowly pour milk and cream into the skillet, whisking constantly. Bring sauce to a simmer and continue to cook, while whisking, until thickened, 2-3 minutes more.

  • 2 cups whole milk
  • 1/2 cup heavy whipping cream

• STEP 18

  Remove sauce from the heat, then add Parmesan and spices. Whisk until combined.

  • 1/3 cup parmesan cheese, shredded
  • 3/4 tsp garlic powder
  • 1/2 tsp salt
  • 1/2 tsp black pepper

• STEP 19

  Pour sauce over the green beans and mushrooms; stir to combine the casserole. Tightly cover the baking dish with aluminum foil.

• STEP 20

  Place baking dish in the oven and bake until sauce is bubbling at the edges, about 20 minutes.

• STEP 21

  Remove foil, scatter the crispy onions on top, and return casserole to the oven. Continue to bake (uncovered) until lightly browned on top, 8-10 minutes more. (Alternatively, you can substitute the homemade crispy onions for 1 cup of French’s Original Crispy Fried Onions.)

• STEP 22

  Remove casserole from the oven and let stand 5 minutes before serving.