Charles’s sister made a variation of this dish as a Thanksgiving side and it was the hit of the meal. We think that cheese adds a special something, so if you tolerate dairy, we highly recommend adding some—though even without it, this still ranks as one of our favorites. Adding chicken makes this a great one-dish meal that is the perfect comfort food and a wonderful casserole to have stashed in the freezer. This one takes its inspiration from a dish in Heidi Swanson’s cookbook Super Natural Every Day.
2 tablespoons butter (or coconut or olive oil), plus more for greasing
1 medium onion, chopped
½ pound assorted mushrooms (we like a mix of shiitakes, baby bellas, and button mushrooms), cleaned and chopped
3 cloves garlic, minced
1 teaspoon fresh tarragon
1 teaspoon fresh thyme
1 teaspoon salt
½ teaspoon black pepper
½ head cauliflower, riced (about 4 cups; see “How to Make Cauliflower Rice”)
3 large eggs
1 cup heavy cream or full-fat coconut milk
2 cups cooked chicken, shredded or chopped into bite-size chunks
½ cup shredded Gruyére cheese (optional)
1. Preheat the oven to 350°F. Grease a 9 × 13-inch baking dish (or another shape of similar capacity).
2. Heat a large skillet over medium heat and add the butter. When the butter has melted (being careful not to burn), add the onion and mushrooms and sauté until the onions are translucent and the mushrooms have softened, 5 to 7 minutes.
3. Stir in the garlic, tarragon, thyme, salt, pepper, and cauliflower and sauté for a minute more.
4. Meanwhile, in a small bowl, whisk together the eggs and cream.
5. Transfer the mushroom-cauliflower mixture to a large bowl and stir in the egg-cream mixture. Fold in the chicken and stir to combine well.
6. Scrape the mixture into the prepared baking dish and cover with foil (see Note).
7. Bake (30 minutes). Top with the cheese (if using) and bake, uncovered, until slightly browned and the casserole is set, 20 minutes longer.
VARIATIONS: For some extra greens, add in 1 cup chopped frozen spinach. If you are a mustard fan, mix in 2 tablespoons Dijon or spicy brown mustard. If you need a vegetarian dish, omit the chicken. There are so many other ways in which you can vary this recipe—give your own version a shot.
NOTE: To freeze this dish, do everything up through step 6. Cover with plastic wrap, allowing it to come directly into contact with the casserole, and layer foil on top of it. Store the casserole in the freezer for up to 1 month. To reheat, place in the refrigerator a day before cooking. On the day you wish to eat the casserole, preheat the oven to 350°F, remove the plastic wrap, and replace the foil on top of the casserole. Bake as directed in step 7. If you are egg-free, we did try making this with flax eggs in place of chicken eggs. While it was still tasty, the flax didn’t hold things together quite the same way that the regular eggs did.