Any squirrel will tell you, acorns are edible! They have been a staple food of the Sonoran Desert for thousands of years. The Tohono O’odham, Akimel O’odham, and other Indigenous peoples of the region eat them roasted, ground into flour, and incorporated into soups and porridges. This recipe is inspired by that tradition.
My French onion-style wild morel mushroom soup recipe is made with onions, red wine and a rich stock. One tablespoon of acorn flour adds a faintly nuttiness. The soup is finished under the broiler with toasted baguette and a blanket of melted Gruyère and Parmesan. If you can’t find fresh or dried morel mushrooms, use any wild or cultivated mushrooms available.
What Is Acorn Flour?
The Emory oak acorn is a variety found in the Sonoran Desert. They are more like a chestnut than a typical acorn and are mild enough to eat roasted directly from the shell. Ground into flour, they produce a nutty, slightly sweet, mildly earthy ingredient that adds depth to soups, stews, and baked goods.
Acorn flour is available at specialty grocers and online. If you are in Southern Arizona in autumn the acorns can be gathered, dried, and ground at home.
Ingredients
- ¼ cup butter
- 3 medium white onions thinly sliced, about 4 cups
- 2 cloves garlic minced
- ½ cup red wine
- 4 cups beef or vegetable stock
- 2 Tbsp tomato paste
- 1 Tbsp acorn flour
- ½ tsp black pepper
- 1 pound fresh morel mushrooms or 1 ounce dried about 10 mushrooms
- 1 demi baguette thinly sliced and toasted
- ¼ cup Parmesan cheese
- 1 cup shredded Gruyere and/or Swiss cheese
Instructions
- Melt the butter in a large Dutch oven or soup pot over medium heat then stir in the onions and garlic to coat. Cook for 15 minutes, or until starting to brown and caramelize. Add the wine then scrape up any brown bits that form on the bottom of the pot with a wooden spoon. Stir in the flour, then the stock, tomato paste, mushrooms and black pepper and cook for 20 minutes.
- Preheat the oven to broil. Ladle the soup into oven-safe bowls, then float a couple slices of baguette on top. Sprinkle evenly with Parmesan cheese then a handful of shredded Gruyere or Swiss. Place in the oven and broil until the cheese is browned and bubbly. Serve immediately.
