Un-Tortilla Soup

This recipe is sort of a blank slate—a deeply flavored, spiced (but not too spicy) broth that allows you to make a perfectly customized bowl of tortilla soup. Well, un-tortilla soup, unless you make a batch of Paleo Tortillas to accompany it—a fantastic idea, really. You can even make multiple batches and freeze the broth in quart-size (946 ml) containers for instant tortilla-soup base later on. It reheats beautifully.
Using dried chillies is easy, despite their potentially menacing appearance. You can find them in Latin sections of many grocery stores or in Latin food markets.

Prep time 25 minutes
Makes about 4 quarts (3.8 liters) of stock

4 dried ancho or guajillo chillies
11/2 large yellow onions, cut into wedges
1 28-ounce (794 g) can diced tomatoes
2 teaspoons whole coriander (or 1 teaspoon ground)
2 teaspoons ground cumin
3 bay leaves
1/2 teaspoon dried thyme
1/2 teaspoon dried oregano
2 teaspoons sea salt
3 quarts (5.7 liters) Simple Chicken Stock
6 cloves garlic, smashed
Suggested add-ins and sides: grilled/shredded chicken or beef, shredded carrots, Southwest Cabbage Slaw, diced avocado, diced jicama, chopped cilantro, hot sauce, or Paleo Tortillas

1 Break the chillies in half and shake out the seeds. Discard the seeds.
2 Submerge the chillies in boiling water and let them soak for 20 minutes until they are soft and pliable.
3 Meanwhile, add the remaining ingredients to a 6-quart (5.7 liter) slow cooker.
4 When the chillies have softened, remove them from the water, discard the stems and any additional seeds, and place them in a food processor. Process until smooth. (If you don’t have a food processor, just chop the chillies very fine.)
5 Add the chili paste to the slow cooker and stir to combine.
6 Cover and cook on low for 4 hours.
7 Strain the stock by removing the large chunks with a large slotted spoon or a spider. Pour the remaining stock through a mesh strainer into a large pot. Return the strained stock to the slow cooker.
8 Place desired soup add-ins into bowls and ladle the stock over the top.