I'm not going to give you a recipe that simply calls for tossing everything into a pot and simmering for 20 minutes, though. I feel that any good dish is built from the bottom up, flavor-by-flavor, and this one especially benefits from that philosophy.
While divine in it's own right, I think the addition of chicken makes it hearty enough for a meal.
Here is the basic recipe, but pay close attention to the method - it's not what you think.
Nacho Mama's Chicken Tortilla Soup
1 small onion - diced
1 small green pepper - diced
2 cloves garlic - minced
8 cups chicken stock
2 cups peeled, seeded and chopped tomatoes
2 cups cooked and chopped chicken breast
1 sprig of epazote - chopped OR 1/4 cup chopped cilantro leaves
1 lime - zested, halved and juiced
1/2 teaspoon cumin seed
1/2 teaspoon dried oregano - rubbed
1 small dried chile such as arbol
8 corn tortillas - cut into strips
1 small avocado - peeled and diced
1 lime - sliced thinly
1/4 cup whole cilantro leaves
1/2 cup shredded Monterey Jack cheese
Cook strips of tortilla in a small amount of oil over medium-high heat until toasted. Set aside on paper toweling to drain.
Toast cumin lightly in a non-stick pan. Cool and powder with a spice grinder. Toasting and grinding the seed makes the flavor deeper. Add the oregano to this and set aside.
Heat a couple tablespoons of neutral oil, like canola, in a large stock pot over medium heat. Add onion and green pepper and cook until onion is translucent. Add minced garlic and stir for a moment. Add stock and tomatoes and simmer until vegetables are tender - about 20 minutes.
Add chicken, oregano and cumin, lime juice, zest and lime halves, cilantro and chile. Simmer for another 20 minutes until flavors blend. Remove chile and lime halves.
Serve in bowls, topped with tortilla strips, lime slices, avocado, cilantro leaves and shredded cheese.
*Note - the version in the photo contains kidney beans, which is not the norm, but is really good.