Place a pizza stone on the bottom rack of the oven. Preheat oven to 450 degrees F.
In a small saucepan heat oil over medium-high heat. Add onion, garlic, and salt; cook about 3 minutes or until onion and garlic are tender. Stir in chili powder and cumin; cook for 1 minute more. Remove from heat; stir in beans and 3 tablespoons of the water. Transfer mixture to a food processor or blender. Cover and pulse with several on/off turns until bean mixture is spreadable but still chunky, adding more water if necessary.
Working with one tortilla at a time, evenly spread a thin layer of the bean mixture on tortilla. Top with 1 to 2 tablespoons of the Easy Enchilada Sauce and 1/4 cup of the Oaxaca cheese. Transfer topped tortilla to the pizza stone. Bake for 4 to 5 minutes or until cheese is bubbly and edges are crisp.
Transfer pizza to a cutting board; let cool for 1 minute. Top with some of the avocado, 2 tablespoons of the queso fresco, 1 tablespoon of the cilantro, and 1 tablespoon of the red onion. Repeat with remaining ingredients to make eight pizzas total.
Easy Enchilada Sauce
In a large saucepan heat oil over medium-high heat. Add onion, garlic, and a pinch salt; cook and stir for 2 minutes. Stir in tomatoes and cayenne pepper. Cook, covered, for 4 to 5 minutes or until tomatoes can be easily mashed. Let cool slightly. Transfer tomato mixture to a food processor or blender. Cover and process or blend until smooth. Return mixture to saucepan. Stir in enchilada sauce, broth, chocolate, and honey. Bring to boiling over medium heat; reduce heat. Simmer, uncovered, about 20 minutes or just until sauce thickens enough to coat the back of a spoon. Season to taste with additional salt.