Cast Iron Green Bean & Mushroom Casserole

This dish has a bit of a history with Tuck’s mom and dad. Tuck’s mom had just finished culinary school and was admittedly a bit of a food snob at the time. It was going to be her first Thanksgiving with Tuck’s dad (this was before Tuck and before marriage) and he insisted on having Green Bean Casserole because it was his favorite. Tuck’s mom gasped in horror that after a year in culinary school something that was mostly made of canned foods was going to end up at the table on her favorite holiday. Was this incredibly snobby? Yes. But she stood her ground because she’s a Taurus. Instead of continuing to bash the infamous Green Bean Casserole, she embraced it as a challenge and cooked it herself. Every year since, she has been responsible for making it for Thanksgiving and has tweaked it to become its very best version of the original classic. At Tuck & Tate, Thanksgiving dinner means a turkey is being fried somewhere. If you celebrate in a similar manner, throw the onions in the fryer after you have finished the turkey. It will save you extra dirty pans and means you can throw them over top at the last second for the ultimate crunchy treat. 

Cast Iron Green Bean and Mushroom Casserole
Serving Size: 10-12 servings                                                                                                      
Prep Time: 40 minutes      Total Time: 1 hour 15 minutes 

Ingredients For The Casserole:

  • 2 lb green beans, ends trimmed and cut in half
  • 1 lb+ mixed mushrooms- we use shitake, crimini, and baby bella 
  • 6 cloves garlic, minced and separated in half
  • 4 tbs butter, separated in half 
  • 1 1/2 cups whole milk
  • 1 1/2 cups chicken stock 
  • 1/3 cup white wine 
  • 2 tsp dijon mustard
  • 2 tbs Worcestershire sauce 
  • 4 tbs flour 
  • salt and pepper to taste 

Ingredients For The Fried Onions:

  • 2 cups vegetable oil (approximate this based on the size of your pot) 
  • 1 large onion, cut in half and sliced thin lengthwise 
  • 2/3 cup flour 
  • 1 tbs salt 
  • 1 tbs garlic powder 
  • 2 tsp cayenne pepper 


  1. Preheat the oven to 375 degrees. 
  2. Heat a large cast iron skillet (we use a 12 inch) over medium high heat. Add the 2 tbs of the butter, half of the garlic, 1/2 cup water, and the green beans to the pan. Cook the green beans for about 5 minutes, so that the water has evaporated and the green beans start to soften. We like this steam and saute method to keep the nutrients in the green beans and to take away an extra pot in the cooking process. Remove the green beans from the pan into a medium bowl, leaving any extra butter in the pan; set aside. 
  3. Add the mushrooms, remaining garlic, and remaining butter to the same cast iron pan. Saute over medium heat until the mushrooms start to release their liquid- about 5 minutes. Stir frequently so that the mushrooms do not stick to the bottom. Remove the mushrooms from the pan to the bowl with the green beans, again, leaving any butter or liquid in the cast iron. 
  4. Add the white wine, dijon mustard, and Worcestershire to the pan. Use a whisk to mix everything together well. Add the flour to the pan to make a roux. Stir for a few minutes, until the roux is a medium brown color.
  5. Add the chicken stock and milk to the pan 1 cup at a time, whisking as you go to prevent lumps of roux from forming in the liquid. Once all three cups of liquid are in the pan, bring the heat to high, until the liquid starts to boil. Add the green beans and mushrooms back to the pan, stir everything well, and season with salt and pepper. This is your one chance to season everything before it bakes- taste and season, stir, and then taste and season again. Put in the oven and bake for 25 minutes. 
  6. **While the cast iron is cooking, heat a large saute pan (with sides) over medium-high heat. Add the vegetable oil to the pan and let it start to get hot. While this is happening, put the sliced onions, flour, and seasonings in a large zip lock bag. Give it all a thorough shake so that the onions are all coated in the flour mix. Use a strainer to strain the onions and remove excess flour. Test the oil with a small onion string- if it starts to sizzle you are ready to add the onions to the pan. Add the onions in small batches so that you don’t overcrowd the pan or reduce the heat of the oil. Saute for 6-8 minutes or until the onions are crispy and brown. Remove from the oil with a strainer onto paper towels to drain. Season with a bit of extra salt. Repeat this as necessary until all of the onions have been cooked. 
  7. Remove the cast iron from the oven. Top with fried onions and serve immediately. 

**This fried onion step can be done ahead of time if you need to knock a few things out earlier in the day. If you do this, add the onions to the top of the cast iron pan with 3-5 minutes left in the cooking time to reheat and get crunchy again. 

3 thoughts on “Cast Iron Green Bean & Mushroom Casserole

  1. Pingback: Thanksgiving 2020 | TUCK & TATE

  2. Pingback: Thanksgiving Dinner 2019 | TUCK & TATE

  3. Pingback: 30 Recipes For Your Thanksgiving Menu | TUCK & TATE

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s