Porcini Mushroom, Greens, and Forbidden Rice Gratin

Superfood has met comfort food in this flavorful and hearty black rice casserole: Porcini Mushroom, Greens, and Forbidden Rice Gratin.  This recipe is vegetarian and easily gluten free.

Comfort Food Meets Superfood

Have you tried black rice (aka Forbidden rice)? Its texture is similar to short grain brown rice, it has an earthy, nutty flavor and sweet undertones. Black rice is considered a whole grain and has more antioxidants than most other rice varieties. Black rice is often considered a superfood because of its high nutritional content (Dr. Axe).

It’s fabulous enjoyed alone, but is absolutely wonderful in this gratin, with coconut milk and in salads.

But lets take a look at porcini mushrooms too. Recipes with porcini mushrooms bring a rich, earthy and umami boost, as well as offer a meaty, chewy texture. They’re high in antioxidents and offer a wide range of health benefits. 

Look for porcini mushrooms at a well stocked grocery. You’ll find them dried in one ounce packets. They’ll need to be rehydrated (or reconstituted) before using them in this recipe. It’s easy to do. 

The Makings of a Black Rice Casserole

This gratin is also considered a casserole. It’s simply layers of various components put together in a deep casserole dish, then baked. The flavors marry to produce a rich and flavorful recipe, hearty enough as a main. We love this recipe with a big salad.

Here’s how to make it (see recipe card below for full details):

• First, reconstitute the dried porcini mushrooms by soaking them in hot water. Drain, chop and set aside. 
• Second, put the black rice on to cook.
• Third, caramelize the onions. 
• Fourth, destem the chard and kale, then cut into ribbons. Cook until wilted. 
• Fifth, toast the breadcrumbs and shred the gruyere. 
• Next, in a mixing bowl mix the mushrooms, black rice, onions, and greens. Transfer to a casserole, top with gruyere and breadcrumbs.
• Last, bake!

While the gratin is baking, now is a good time to whip up a big leafy green salad, and warm the bread. 

More About the Ingredients

Porcini (say it with me! ‘por-tchee-knee’) mushrooms can be found year-round in dried form, typically in 1 oz bags. I find them at my local Co-Op, along with forbidden rice (AKA purple or black rice). Either ingredient can be found at Amazon.com here and here if you’re unable to find them locally.

This gratin is packed with superfoods.  For example, mushrooms are powerful in immune system support and are protective against cancer. Forbidden rice rivals blueberries in anthocyanin, an antioxidant. It has anti-inflammatory properties and is protective against heart disease and cancer. No doubt our immune system can use all the support it can get in our modern world.

A Few Recipe Notes

• Porcini mushrooms and forbidden wild rice pair well because they both impart a nutty, umami flavor while the porcini also add a firm, meaty texture. Gruyère adds a bit of richness and indulgence.
• This black rice casserole calls for both Swiss chard and kale. However, use one or the other, or both! 
• This recipe is hearty enough to be served as a main, and would be lovely center stage on a holiday table. 
• Make it gluten free by using gluten free breadcrumbs. 
• Freezer Friendly? Yes please! This black rice casserole freezes with ease. Simply cool completely and freeze in a covered container for up to two weeks. Thaw in the fridge, then reheat in a 350F oven. 

More Porcini Mushroom Recipes to Love

• Lentil Mushroom Cabbage Roll Soup
• Cottage Pie
• Mushroom Stuffed Cabbage Rolls

Print Recipe

Porcini Mushroom, Greens and Forbidden Rice Gratin

Servings:5 -6 as Main Dish

Calories:612kcal

Author:Vanilla And Bean

This gratin makes a hearty main dish or a delicious side. It won't last long! This recipe is vegetarian and easily gluten free.

Look for porcini mushrooms on the natural food isle, dried. They'll need to be reconstituted.

Ingredients

• ▢ 1 oz Dried Porcini Mushrooms 28g
• ▢ 1 C Forbidden Black Rice 194g
• ▢ 4 1/2 C Yellow or Sweet Onions sliced into thin 1/2 moons (about 2 large onions) 344g
• ▢ 1 Tbs Coconut Oil Virgin, Unrefined* (see note)
• ▢ 2 Tbs Butter divided
• ▢ 1 tsp Sea Salt divided
• ▢ 1 tsp Pepper divided
• ▢ 2 1/2 C Kale, chopped 104g
• ▢ 2 C Rainbow or Swiss Chard, chopped 118g
• ▢ 1 1/2 C Bread Crumbs** Gluten Free if needed 116g, see note
• ▢ 8 oz Gruyere grated, 227g
• ▢ 1/2 tsp Fresh Thyme chopped
• ▢ 1/4 tsp Nutmeg
• ▢ Fresh Thyme for Garnish

Instructions

• Bring 2 C of water to boil. Place porcini in heat proof bowl and pour the boiling water over the porcini. Cover for 30 minutes to soften the porcini.
• Put the black rice on to cook. Fill stock pot with rice, a pinch of sea salt and 2 C water. Bring to a boil, turn the stove to low, cover and cook for about 30 minutes. When cooking is complete, the rice will be tender and no water will remain. Place rice in large mixing bowl. Set aside.
• Cut the onions in half and slice length wise so that your slices are thin and long. Melt the coconut oil and 1 Tbs butter in a large non stick sauté pan. Place the onions in the pan with 1/2 tsp salt and 1/2 tsp pepper. Cooking on medium to low heat, these will take about 30 minutes to caramelize. Don't rush them else they'll burn. Low and slow here. Stir occasionally.
• For the greens, wash the kale and chard. De-stem the kale. Ribbon the greens by rolling the leaves up, length wise, then cutting about 1/2" ribbons. Then, rough chop the ribbons in 1/2. Set aside.
• Melt 1 Tbs butter and mix it into the bread crumbs. Set aside.
• Preheat the oven to 375F (190C). After the porcini have softened, strain the porcini through cheese cloth, reserving the broth. Squeeze the cheese cloth so that the broth is extracted from the porcini. Give the mushrooms a good rinse in a sieve to make sure they are free from debris. Rough chop the porcini and place them in the large mixing bowl with the rice. Strain the broth through the sieve again. Measure out 1/3 C (80g) of the broth and set aside. Freeze or refrigerate the remaining broth for future use.
• When the onions are done caramelizing, add the greens to the sauté' pan, with the onions. This may be done in batches if needed. When the greens just start to wilt, pull them from the pan and put them in the large mixing bowl with the cooked rice and porcini.
• In the large mixing bowl, mix all the rice, porcini, greens, caramelized onions, 1/2 the grated gruyere, thyme, nutmeg, and 1/2 tsp salt and 1/2 tsp pepper. Mix to evenly distribute the ingredients. Taste to check seasoning. Now is a good time to adjust if necessary.
• Prepare a 3-4 Quart casserole by spraying it with cooking spray. Pour the rice/greens mixture in the dish, smoothing it out. Pour a 1/3 C (80g) of the broth over the mixture. Spread the remaining gruyere over the top, then top the gratin with the breadcrumbs. Bake uncovered for 25 minutes. Garnish with fresh, chopped thyme.
• Store in a covered container for up to three days.

Notes

*I use unrefined coconut oil for most of my cooking and baking. You will not taste coconut in the recipe. I reserve olive oil mostly for roasting, salad dressing, drizzling and dipping, but it can be subbed here if needed.

**For homemade breadcrumbs, process five pieces of bread in a food processor, then bake the crumbs at 325F (163C) for about 30 minutes, stirring once, to dry them out. Use gluten-free if necessary.

Adapted from The Smitten Kitchen Cookbook.

Nutrition is provided as a courtesy and is an estimate. If this information is important to you, please have it verified independently.

Calories: 612kcal | Carbohydrates: 74g | Protein: 25g | Fat: 25g | Saturated Fat: 15g | Cholesterol: 62mg | Sodium: 948mg | Potassium: 699mg | Fiber: 6g | Sugar: 9g | Vitamin A: 4799IU | Vitamin C: 55mg | Calcium: 617mg | Iron: 3mg

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