1 teaspoon
Mexican hot sauce, plus more to taste, such as Tapatío
1 tablespoon
whole milk, (optional)
Method
Make the tostadas. Heat a large skillet over medium heat. Add the chorizo and cook, breaking up the meat with a wooden spoon, until browned, about 6 minutes.
Meanwhile, make the crema. In a small bowl, whisk together the sour cream, lime juice, oregano, cumin, garlic powder, sea salt, and hot sauce until smooth. If using, stir in the milk 1 teaspoon at a time, until the sauce reaches your desired consistency.
Add the refried beans to the skillet with the chorizo and stir until evenly combined. Cook, stirring occasionally, until beans are warmed through, about 2 minutes.
Evenly top the tostada shells with the bean and chorizo mixture. Top each with cotija, lettuce, pico de gallo, and guacamole. Serve the tostadas with a drizzle of crema, a squeeze of lime, and a few dashes of hot sauce, if desired.