Slow cooker swiss chard & lentil stew

From Cook's Illustrated: The Best Make-Ahead Recipe.

Why this recipe works:
After some preliminary testing for our slow-cooker lentil and Swiss chard stew recipe, we decided that large brown and green lentils did the best job of retaining their texture, shape, and flavor through the all-day simmer. As the lentil and Swiss chard stew recipe progressed, we realized it needed more flavorful components to boost the lentils and chard, which, admittedly, tasted pretty thin. After testing a variety of additional ingredients, we most liked the earthiness of mushrooms—in particular, meaty portobello mushrooms pumped up with dried porcini.

PREP-AHEAD TIPS: You can store the following ingredients together, with the exception of the chard leaves:
1. Cook the onion-chard stem mixture as described in step 1, then transfer the mixture to an airtight container and refrigerate; prep the chard leaves and refrigerate.
2. Prep the carrots and refrigerate.
3. Prep the portobellos and refrigerate.
4. Pick over and rinse the lentils and refrigerate.

Be sure to choose large green or brown lentils and avoid red lentils or lentils du Puy, both of which will overcook. Carefully sort through the lentils to remove small stones and pebbles and then rinse.

Serving Size

Serves 6 to 8

Ingredients

2 tablespoons vegetable oil
3 medium onions , minced
1 pound Swiss chard , stems and leaves separated (see illustration below); stems cut into 1/4-inch pieces and leaves chopped coarse
6 medium garlic cloves , minced or pressed through a garlic press (about 2 tablespoons
Salt
6 cups vegetable broth
1 pound carrots , cut into 1-inch chunks
1 (15-ounce) can tomato sauce
12 ounces portobello mushroom caps , gills removed, cut into 1/2-inch chunks
7 ounces brown or green lentils (1 cup), rinsed and picked over
2 bay leaves
1 tablespoon minced fresh thyme leaves , or 1 teaspoon dried
1/2 ounce dried porcini mushrooms, rinsed and minced
1 tablespoon balsamic vinegar
Ground black pepper
Extra-virgin olive oil (for serving, optional)

Recipe Directions

Heat the oil in a 12-inch nonstick skillet over medium heat until shimmering but not smoking. Add the onions, chard stems, garlic, and 1/4 teaspoon salt and cook until the vegetables are softened and lightly browned, 10 to 12 minutes.
Transfer the onion mixture to the slow cooker insert and stir in the broth, carrots, tomato sauce, portobello mushrooms, lentils, bay leaves, thyme, and porcini mushrooms until evenly combined. Cover and cook on low until the soup is thickened and the lentils are tender, 8 to 10 hours. (Alternatively, cover and cook on high for 5 to 7 hours.)
Remove and discard the bay leaves. Puree 2 cups of the soup in a blender until smooth, then stir back into the slow cooker insert. Stir in the chard leaves, cover, and continue to cook until the leaves are wilted and tender, 10 to 15 minutes longer. Stir in the vinegar, season with salt and pepper to taste, and serve.

Technique: Preparing Chard
Hold each leaf at the base of the stem over a bowl filled with water and use a sharp knife to slash the leafy portion from either side of the thick stem or hold the leaves, stacked, on a cutting board and run the knife along the sides of the stem.

Technique: Removing the Gills from Portobello Mushrooms
It is necessary to remove the black gills from the portobello mushrooms because they made the stew muddy in appearance. Using a soup spoon, scrape and discard the dark-colored gills from the underside of each mushroom.

I top mine with fried egg and some Sriracha!
Emily George (Happy Hollow Farm CORE group member)