Gather ingredients so that you have everything close at hand on the counter or table. If using fresh green beans, trim ends as needed. Slice mushrooms. Chop the sweet onions. You decide whether to coarsely chop the onions or mince them. I have done it both ways.
If using frozen green beans, cook in microwave according to package directions. If using fresh green beans, place in a large microwavable dish. Add in 2 tablespoons water to create steam. Cook on high for 10-12 minutes until crisp tender.
Transfer green beans to a large serving dish.
To Make the Mushroom Sauce:
Meanwhile in a large skillet, heat olive oil and butter. Add sliced mushrooms and chopped onions and saute until tender 4-6 minutes.
Mix all-purpose flour into the melted fat to create a roux. Slowly add milk, stirring until it thickens 3-5 minutes. Season with dried thyme, kosher salt, and freshly ground black pepper.
Spoon sauce over green beans and top with slivered almonds. This recipe will serve 10-12 people.
An Alternative Way to Serve This Dish

If cream sauce is not your thing, you can easily adapt this recipe to serve without it. Simply, skip adding the all-purpose flour and milk in Step #4, and go ahead and add the green beans to the sauted vegetables. Gently stir together to incorporate and then season with dried thyme, kosher salt and freshly ground black pepper. You may then add the slivered almonds to the top (or skip this, too).
See more Side Dishes Here. View more Holiday Dishes Here. Browse Potluck Recipes Here.